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机械制造技术基础课程设计（英文要点·大三大四）
核心内容
Basic concepts:
This course is for designing a milling jig for a workpiece.
Explanation of concepts:
Above picture is the milling jig , and the red part is the workpiece, the black part is the feeler block(对刀块).What we have to do is to design the jig to fix the workpiece.
Fist, we have to know that the jig need to limit the degree of freedom of the workpiece, and all the six degree of freedom need to be limited. So at the left of the jig, i choose a long V-type block . And on the right, is a movable V-type block, which have thread on it and can clamp the workpiece by turn the hand bar. These two parts limit five degree of freedom, as for the left one, i choose to use the self-support ball(自支撑球体). The self-support ball can’t and only can’t move up and down, and it can make any movement on the other direction, so it can only limits one degree of freedom. Then the six degree of freedom are all limited. The two U-type grooves on the blue part is for fixing the jig on the milling machine. All the parts are the standard parts, the parameter of them can be found on the book.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：机械制造技术基础课程设计
微生物学实验
核心内容
· 牛肉膏蛋白胨培养基（Beef extract peptone medium）
· 配方（per 1000 mL）：牛肉膏（beef extract）3 g、蛋白胨（peptone）10 g、NaCl 5 g、琼脂（agar）15–20 g、水 1000 mL、pH 7.4–7.6
· 制备流程：
1. 称量：按配方比例依次准确称取牛肉膏、蛋白胨、NaCl 放入烧杯。
2. 熔化：先加入少于所需量的水，玻璃棒搅匀，石棉网上加热溶解。
3. 调 pH：用 1 mol/L NaOH 或 1 mol/L HCl 调整至 pH 7.4。
4. 分装：按实验要求分装入试管或三角烧瓶。
5. 加塞：试管口或三角烧瓶口塞上棉塞。
6. 灭菌：1.05 kg/cm²、121 ℃、20 min 高压蒸汽灭菌。
7. 搁置斜面：灭菌后试管培养基冷至约 50 ℃，将试管棉塞端搁在玻棒上制成斜面。
· 易考点：pH 7.4–7.6 与调 pH 至 7.4 的差异；琼脂为凝固剂，用量 15–20 g/L；灭菌参数（1.05 kg/cm² ≈ 0.103 MPa，121 ℃，20 min）。
· 实验室常用消毒灭菌方法（Disinfection and sterilization methods）
1. 干热灭菌法（dry heat sterilization）：恒温干燥箱内 120 ℃–170 ℃，保持 90–120 min。
2. 湿热灭菌法（moist heat sterilization）：高压蒸汽锅 1.05 kg/cm²、121 ℃、20–30 min（原文“3℃”系笔误/扫描噪声，应为 121 ℃）。
3. 射线消毒法（radiation disinfection）：紫外线灯照射；紫外线为低能量电磁辐射，可杀灭多种微生物。
4. 过滤除菌法（filtration sterilization）：液体或气体通过微孔滤膜，大于孔径的微生物颗粒被阻留而除菌。
5. 化学消毒剂消毒法（chemical disinfection）：甲醛（formaldehyde）、高锰酸钾（potassium permanganate）、70%–75% 乙醇（ethanol）等。
6. 抗生素抑菌法（antibiotic inhibition）：用青霉素（penicillin）等抗生素抑菌/灭菌。
· 分类维度：干热 vs 湿热；物理法（热、射线、过滤）vs 化学法（消毒剂、抗生素）。
· 易考点：干热与湿热温度—时间对应关系；紫外线穿透力弱、仅表面消毒；过滤除菌适用于热不稳定液体。
· 微生物的分离与纯化技术（Isolation and purification of microorganisms）
· 两种平板接种培养方法：
1. 取土壤：取表层 5–10 cm 处土样放入无菌袋。
2. 制备稀释液：无菌条件下取 1 g 土样加入 99 mL 无菌水摇匀，得 10⁻² 土壤悬液；用移液枪吸 10⁻² 悬液 1 mL 加入 9 mL 无菌水得 10⁻³ 稀释液，依次重复制成 10⁻³–10⁻⁷ 稀释液。
3. 平板接种培养：
· 稀释涂布平板法（spread plate method）：取对应稀释梯度稀释液，在酒精灯旁倒入固体培养基平板。
· 平板划线法（streak plate method）：用接种环挑取 10⁻² 土壤悬液，在固体培养基平板上划线分离。
4. 培养：接种后平板倒置，放入恒温培养箱培养。
· 应用：分离具有特殊功能的微生物、优良菌种及纯化被污染的菌种等。
· 易考点：稀释倍数计算（1 g→99 mL 为 10⁻²；1 mL→9 mL 为 10 倍稀释）；平板倒置培养的目的（防冷凝水滴落、防污染）；两种接种法的适用场景差异。
参考：来源：微生物学实验.png｜专业：生物科学｜课程：微生物学实验
机械制造技术基础综合实验（英文要点·大三大四）
核心内容
Basic concepts:
This experiment is a casting experiment, we build casting moulds, and cast simple parts. All these work are making in our engineering training center.
Explanation of concepts:
The mould part are made by us, the casting part is made by our teacher for our safety.
First we should make a mould. We should put the drag box on the operating platform first, then put some wet sand in it, then compact it. Then we put the model of the workpiece in the drag box on the compacted sand, and the small part of the model should toward down. Then we fill the drag box to full with wet sand, and compact it. After that, we clean the sand over the top plane of the drag box and make the top plane of the sand smooth. Then we put some tap sand(分型砂) on it . And stand a tube beside the model. Then we put the cope box on the drag box, and fill it with wet sand and compact it, too. Then clean the top plane of the cope box and make some air hole on it. Then take out the tube in it , the pour gate is formed. Then we make a sign on the cope box and the drag box , for assembling them again. Then we put the cope box away from the drag box, finish the pouring gate in the drag box, and take the model out . Then we can assemble the two box again. Last, our teacher pours melted metal in to the mould through the pouring gate.
Measuring the hardness of the workpiece:
Rockwell hardness(洛氏硬度)：when the HB is larger than 450, we use HR, usually is using a diamond cone with 120°apex angle, press it into the surface of the measured workpiece under a certain load and keep it a certain time, and then get the hardness through measuring the depth of the indentation.
HRA D+588.4N for hard alloy, steel sheet.
HRB 1.5875mm steel ball+980.6N for some soft material, mild steel.
HRC D+1471N for casting iron, quenching steel.
Brinell hardness(布氏硬度): press a material ball into the surface of the measured material.
HBS quenching ball for the material whose hardness is lower than 450, such as mild steel.
HBW hard alloy ball for the material whose hardness is lower than 650.
170 HBS 10/1000/30 10mm d quenching ball, 1000Kg pressure force, metain 30min the HB is 170.
Vickers hardness(维氏硬度): with a pyramis diamond, with 136° angle between face and face, press into the surface.
185 HV5 185 is hardness. 5 is the load, 5Kg.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：机械制造技术基础综合实验
机械制造技术基础（英文要点·大三大四）
核心内容
Basic concepts:
In this course, i mainly learned what is productive process, what is engineering progress, the types of manufacturing and the datum which are used in engineering progress. Then i learned the process of metal cutting, the methods and devices used in machine manufacturing and fixture.
Explanation of concepts:
Production process(生产过程): all the processes from the raw material into the factory to the end product comes out.
Engineering process(工艺过程): in the production process, all the change of the workpiece.
Types of manufacturing: single-production production, volume production, mass production.
Datum:
The datum(基准) ,which is used in engineering process, is called engineer datum(工艺基准). Include process datum, location datum, measuring datum and assembly datum.
Process datum(工序基准): used to determine the basis of the surface dimensions(加工表面尺寸), shape and position of the process.
Location datum(定位基准): used as a reference for locating.(may not exist)
Measuring datum(测量基准): during or after the manufacturing of the workpiece , the datum used for measuring the size and shape.
Assembly datum(装配基准): a datum used to determine the relative of the part of component in the product when assembly.
Metal cutting process:
The basis of cutting:
Vc : cutting velocity, the velocity of the main cutting edge relative to the workpiece.
Vf : feed velocity, feed is the motion making the machined surface complete. The velocity of feed called feed velocity (mm/r).
There is a formula for the Vc:
n: rotate speed of the workpiece
d: max of the diameter of the workpiece
Three keys of cutting: cutting velocity Vc, feed quantity, back engagement of the cutting edge(背吃刀量).
Feed quantity: the relative displacement between the tool and workpiece on the feed movement direction.
Back engagement of the cutting edge: it is the vertical distance between the machined surface and waiting machining surface.
dw is the diameter of the waiting machining surface.
dm is the diameter of the machined surface.
The structure of the cutting tool:
Rake face(前刀面):the cutting chips flow along this surface;
Major flank(主后刀面): the opposite surface of the transitional surface of the workpiece;
Minor flank(副后刀面): the surface which is opposite to the machined surface of the workpiece;
Major cutting edge(主切削刃): the intersecting edge of rake face and major flank, used to finish the cutting work;
Minor cutting edge(副切削刃): the intersecting edge of rake face and minor flank, working with the major cutting edge to finish the cutting work , then the machined surface is finished;
Tool nose(刀尖): a cutting edge connecting the major cutting edge and the minor cutting edge.
When only the major cutting edge involves into the cutting work, it is called free cutting, or it is called non-free cutting.
Annotation angle of cutting tool(刀具角度标注):
1, base plane(Pr 基面): the plane through a specified point on the major cutting lip and is vertical to the direction of the cutting velocity.
2, cutting plane(Ps 切削平面): the plane is through a specified point on the major cutting edge and is tangent to the major cutting edge, meanwhile the plane is vertical to the base plane of that point.
3, tool orthogonal plan(Po正交平面): the plane is through a specified point on the major cutting edge and it is vertical to the base plane and cutting plane of that point.
There are five annotation angles.
1, rake angle(γ0前角): the angle between the rake face and base plane, which is measured in the orthogonal plane. When the rake face is downside, it is positive, or it is negative.
2,clearance angle(α0后角): the angle between the major flank and cutting plane which is measured in the orthogonal plane usually it is positive.
3, major cutting edge angle(Kr主偏角): the angle between the projection of the main cutting edge on the base plane and the direction of the feed motion, which is measured in the base plane.
4,minor cutting edge angle(K’r副偏角): the angle between the projection of the minor cutting edge on the base plane and the negative direction of the feed motion, which is measured in the base plane.
5, tool cutting edge inclination(λs刃倾角): the angle between the main cutting edge and base plane, which is measured in the cutting plane, when the tool nose is the highest point, it is positive.
Tool material:
We need high hardness and wear resistance , enough strength and toughness, and high heat resistance material. Such as high-speed steel(W18Cr4V), hard alloy ,cubic boron nitride(CBN立方氮化硼) and diamond.
The deformation of metal in cutting process:
068580Ι, first deformation area: the metal moves toward right and into AO, start to deform. When it get MO, the shear slip is completed. The area between AO and MO is the first deformation area. The main character is shearing deformation along the slip line and the work hardening(加工硬化).
ΙΙ, the second deformation area: the chip go out along the rake face , the rake face squeeze and rub the chip, make the area of the chip next to the rake face become metal fibrosis(金属纤维化).
ΙΙΙ, the third deformation area: the machined surface is squeezed and rubbed by the flank, and become metal fibrosis and work hardening.
The built-up edge(BUE积屑瘤)：
In the cutting process, there is a strong friction between the cutting chip and the rake face, when the temperature and the pressure is high, the cut material will weld on the rake face, and it will make the temperature and the pressure higher, there will be more and more material weld on it, then the major cutting edge will be thicker, it will become the built-up edge.
The built-up edge will make the rake angle larger, lower the cutting force, make the cutting thickness larger , make the surface quality lower, make the life of the cutting tool shorter.
If we want to avoid the built-up edge, we should choose the right cutting speed, avoid the speed that may cause the built-up edge, choose good-quality cutting fluid(切削液), choose larger rake angle, make the pressure between the chip and the rake face lower, and choose the high-hardness material,which may cause less work hardening.
We use the medium carbon steel as an example, when the cutting speed is lower than 2m/min, there will be no BUE; when the speed is 2~30m/min, the temperature of cutting is 300℃, the BUE is largest; when the speed is 120m/min, the temperature is higher than 800℃, the BUE will disappear.
So usually , under the maximum temperature the tool can hold, improve the velocity of cutting as fast as possible, or using the very low speed.
Types of cutting chip(切屑类型):
1,continuous chip(带状切屑): the inside of the chip is smooth and the outside is lanose(毛绒状). Plastic metal, the cutting thickness is small, high speed and the rake angle is large.
2,segmental chip(节状切屑): the outside is like serration(锯齿) and inside have crack(裂纹).Cutting speed is low, cutting thickness is large, rake angle is small.
3, granular chip(粒状切屑): the cutting force on the shearing plane is larger than the breaking strength of the material, the element of the chip fall from the workpiece.
4,breaking chip(崩碎切屑): when cutting brittle metal(脆性金属), the chip will fly away from the workpiece.
Controlling the type of the chip:
1,use chip breaker(断屑槽);
2,change the angle of the cutter, make the major cutting edge angle larger, make the rake angle smaller;
3,change the cutting quantity, make it small.
Cutting force(切削力):
F(resultant force合力): the vector sum of the Fp , Fc and Ff.
Fp(back force背向力): parallel to the base plane, vertical to the feed direction.
Fc(major cutting force主切削力): vertical to the base plane.
Ff(feed force进给力): parallel to the base plane, parallel to the feed direction.
Fc>Ff>Fp Fp=(0.15~0.7)Fc Ff=(0.1~0.6)Fc
The cutting force is relative to the material of the workpiece, cutting quantity, the geometric parameter of cutting tool, cutting-tool wear, cutting fluid(切削液) and the material of the cutting tool.
Cutting heat(切削热):
In the cutting process, 98%~99% of the energy change into cutting heat.
The elements affect the abstract heat:
1, thermal conductivity(传热系数) of the workpiece;
2, thermal conductivity of the cutting tool;
3,medium around it.
Life of cutting tool:
The time from the tool begin to work until it get the wear stander.
,,, are the coefficient, can be found in tables in the books.
Choice of the geometric parameters of cutting tool:
Rake angle: increase rake angle, decrease the deformation of cutting, cutter force and cutting temperature. But it can not be too large, or the life time of cutting tool will be shorter.
Clearance angle:the main function of the clearance angle is to decrease the friction between the major flank and the workpiece. Increasing the clearance angle can decrease the friction, make the machined surface have better quality, and make the life of the cutting tool longer. But it can’t be too large as well, or it will affect the cutting heat, there will be too small area to abstract the heat.
Cutting edge angle: decreasing the major cutting edge angle and the minor cutting edge angle can decrease the roughness of the surface, increase the strength of the tool nose and the life time.
Tool cutting edge inclination: changing the tool cutting edge inclination can change the direction of the chip flow.
Machining method in mechanical manufacturing:
According to the change of the mass of the material △m,
If △m<0, it is material removal process, such cutting, milling;
If △m>0, it is material accumulation process, such as welding, casting;
If △m=0, it is material forming process, such as forging(锻造).
The model of the machine tool:
The model of the machine tool includes base part and auxiliary part.
For example,
Fixture(夹具):
The function of the fixture:
1, decrease the mismachining tolerance, increase the work accuracy;
2, increase production efficiency;
3, decrease the labor intensity;
4, widen the work range of the machine tool;
The component of the fixture:
1,setting element(定位元件); 2,clamp device(夹紧装置);
3, the tool components(对刀元件); 4, connecting element(连接元件);
5,other elements(其他元件); 6,specific folder(夹具体).
The fixture should limits six degree of freedom of the workpiece.
This part will introduce in《Course exercise for basis of Manufacturing Technology》.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：机械制造技术基础
控制工程（英文要点·大三大四）
核心内容
Basic concepts:
in this course, i mainly learned open loop system and closed loop system, Laplace transform and transfer function, the time domain response analysis of the system, frequency domain characteristics analysis of the system.
Explanation of concepts:
Open loop system:
The open loop system has no feedback function. The output of the system has no impact on the controlled object. So open loop system is generally only used in ignoring the external influence and some lower precision situation.
Closed loop system:
The closed loop system has feedback function, the output of the controlled object returns to the input of the controller in a certain way and has impacted on the controller and controlled object. The output signal will be compared to the ideal output, and then controller will adjust the state of the system. It is high accuracy, but with higher cost.
The feedback: the output has impacted to the input.
The positive feedback: it is the output quantity added on the input quantity, result in that the output signal will larger and larger. For example, nuclear reaction. One nucleus(原子核) meet a neutron(中子), then the nucleus becomes into two nucleus and releases two or more neutrons which will meet more nucleus, so the reaction will more and more acute.
The negative feedback: it is the input quantity minuses the output quantity, make the error gradually reduce to zero. Negative feedback is a common method of automatic control system. For example, the temperature regulation system of our bodies. It is a typical negative feedback, when the temperature of our bodies is too high, there will be a signal to tell out brain to reduce the temperature of our bodies , the opposite is the same.
Laplace transform:
Laplace transform can converts mathematical calculus operations(运算) into algebraic operation of linear differential equation(线性微分方程).
Condition: when t<0, f(t)=0; when t ≥0, f(t) is sectional continuous.
The growth rate of f(t) is less than one exponential function(指数函数).
For example,
s is the complex variable, s=σ+jw,
σ is the real part, jw is the imagining part(虚部), σ and w is real number(实数).
F(s) is the Laplace transform of f(t), s is the independent variable(自变量).
F(s) is the imagine function(象函数), f(t) is the original function.
The Laplace transform is more convenient for calculating.
Superposition theorem(叠加定理):
There are some theorems of the calculation of the Laplace transform, one of the most useful is the superposition theorem.
Inverse Laplace transform(拉氏逆变换):
If we already know the imagine function F(s) and seek for the original function , then the function can help us find the original function is called inverse Laplace transform.
But we seldom use this function to get the original function , it is too complex.
Usually, we look up the table of the Laplace transform.
Transfer function(中间函数):
Under zero initial conditions, the ratio of Laplace transform of output and Laplace transform of input.
Zero initial condition: when t=0, the input is zero, and the output is zero.
Transfer function is C(s) is the Laplace transform of the output. The R(s) is the Laplace transform of the input.
For example,
The proportional component(比例环节),
c(t)=Kr(t) G(s)=C(s)/R(s)=K K is the amplification coefficient(放大系数).
s=-3 C(s)=0 ,-3 is the null point(零点)
s=-4 C(s)=∞,-4 is the pole point(极点)
The time domain response of the system analysis:
The time domain response of the system analysis is that under the external action or the input action, the functional relationship of the output and time is called time response of the system.
The time response of the first-order system:
The general form of differential equation:
T: time constant; c(t): output signal;
r(t): input signal.
Transfer function:
For example, the RC circuit is one of the first-order system.
The unit step response of the first-order system(一阶单位阶跃响应):
Inverse Laplace transform of output:
The unit impulse response of the first order system(一阶单位脉冲相应):
-4318025400
Inverse Laplace transform:
The unit slope response of the first-order system(一阶斜坡响应):
Inverse Laplace transform:
Second-order system:
Such as the RLC circuit, the differential equation of it is :
Standard form of the differential equation of the second-order system:
The time constant of the second-order system:
The relative damping ratio(相对阻尼比):
So the transfer function of the second-order system is :
Let the
And we can get the standard form of the transfer function:
There are four types of second-order system:
1,(0<ζ<1) under-damped second-order system(欠阻尼系统)；
2,(ζ=0) non-damped second-order system(无阻尼系统);
3,(ζ>0)over-damped second-order system(过阻尼系统);
4,(ζ=1)critical damping second-order system(临界阻尼系统).
The four types are not the key points of this course, we didn’t learn them very detail, only know what they are, that is all.
Frequency domain characteristics analysis of the system:
Frequency domain method is based on the frequency characteristics or frequency response of the system ,it is a graphical method.
Ti consists of amplitude-frequency characteristics and phase frequency characteristics.
Frequency characteristic is the radio of amplitude and the phase difference of the output and input quantity, and the will change with the frequency change. We can draw the curve in the coordinate system, clearly see the amplitude ratio and phase difference change with frequency change.
This part is not the key point, so i just know this little.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：控制工程
液压与气压传动（英文要点·大三大四）
核心内容
Basic concepts:
In this course, i mainly learned the advantages and disadvantages of hydraulic transmission, hydraulic pump, hydraulic transmission actuator components, hydraulic control valve, hydraulic basic circuit and some understanding knowledge about pneumatic transmission.
Explanation of concepts:
Hydraulic transmission uses liquid as working medium and uses liquid pressure to transfer the energy.
Composition of hydraulic transmission system:
1, power element, such as hydraulic pump. It transforms the input mechanical energy to the oil pressure energy.
2, actuator, such as hydraulic cylinder and hydraulic motor. It transforms the oil pressure energy to mechanical energy.
3, control element, such as hydraulic valve. It can control the direction of flow, the degree of the pressure and the volume of the flow.
4, auxiliary element, such as oil filter, it can filter impurities(去污).
5, working medium, usually we use the hydraulic oil.
The advantage and disadvantage of hydraulic transmission:
Advantage:
1, light weight, compact structure, small inertia(惯性);
2,it has a wide range of continuously variable(无级变速);
3,convenient operation, easy to control;
4,good security, easy to realize overload protection, easy to dissipate heat;
5,many parts are standard parts, easy to change and fix;
6,good rigidity(好的刚性);
7,easy to achieve linear motion.
Disadvantage:
1, power loss is large; 2, pollute the environment;
3,systematic risk of cracking; 4, higher cost;
5, the demand of using and maintenance technology is higher.
Hydraulic shock(液压冲击): when the speed suddenly become fast or towards to the opposite direction, there will be a very high pressure in the system and some impact. It may hurt the system.
Hydraulic cavitations(空穴): when the speed in the system suddenly become fast, and the oil supply can not meet the requirement, there will be a negative pressure in the system, the air in the oil will come out and become into a bubble, when the bubble go into some high pressure elements, it will break quickly, the oil around will fill the place quickly and generate an impact, cause noisy and shock, hurt the elements.
Hydraulic pump:
The working principle of hydraulic pump is by the change of the sealed vessel volume. Volume increasing is the oil absorption process, the hydraulic oil under the pressure of atmosphere move into the oil pump. Volume decreasing is the oil pressuring process, drain the oil out of pump
Left picture is the graphic symbol of pump.
There are some data of a pump:
Volumetric efficiency(容积效率):
q----- the actual flow
qt-----the theoretical flowfalse
Mechanical efficiency(机械效率):
Tt----- theoretical torque(理论转矩)
T----- actual torque
Overall efficiency(总效率):
Po----- output power
Pi----- input power
There are mainly three kinds of pumps, gear pump, vane pump(叶片泵) and ram pump(柱塞泵). The gear pump is the widely used. The ram pump is always high-pressure pump. I mainly learned the gear pump in this part. The gear pump depends on the closed volume of the meshing gears to realize oil absorption and oil pressure. It is widely used in the low pressure system.
Leakage(泄漏):
1, the gear side clearance leakage is the largest account, for about 70%~75% of the total leakage;
2, the top clearance leakage of the gear;
3, the tooth meshing clearance leakage.
Entrap phenomenon(困油现象):
Part of the oil is trapped in a closed vessel between two pairs of tooth. It can cause high temperature, high pressure. We can make a pair of rectangle unloading groove(卸荷槽) on the cave to solve the problem.
Advantage: simple structure, easy to manufacture,low cost, small size, light weight, reliable work.
Disadvantage: large flow and pressure pulse, large noise.
Hydraulic transmission actuator:
I mainly learned hydraulic cylinder and hydraulic motor. They transform the pressure of liquid to mechanical energy and the output.
The main output of the cylinder is linear motion and force.
The main output of the motor are continuous rotary motion and torque.
Hydraulic cylinder includes single-acting cylinder and double-acting cylinder, these two kinds cylinder are all driven by the pressure of liquid.
It has simple structure and reliable work.
Hydraulic motor:
Classification: High speed hydraulic motor and low speed hydraulic motor.
Efficiency of the hydraulic motor:
High speed hydraulic motor: high speed, quick response, quick action but the output of the torque is small. the P is fixed, so when the n is larger ,the T is smaller.
Low speed high torque hydraulic motor: the speed is very low, the torque is very large, commonly used for engineering machinery and mining machinery.
Hydraulic control valve:
The function of the valve is to control the direction of flow, the degree of the pressure and volume of flow.
The valve can be divided by the function into three kinds: direction control valve, pressure control valve, flow control valve.
Direction control valve:
It includes check valve(单向阀), change valve(换向阀) .
The function of the check valve: restrict the direction of the flow, it can only flow in one direction.
The classification of the change valve:according to the channel and the work position. For example,
The working principle of the directional valve: using the transformation of relative location of valve cove and valve body to determine the on or off of the tube.
Pressure control valve:
This kind of valve includes relief valve(溢流阀), pressure reducing valve(减压阀), sequence valve(顺序阀), pressure switch(压力继电器).
Relief valve: stabilize the inlet pressure and make sure the safe of the pressure of the system. It can be divided into two kinds, one is the directly operated type relief valve(直动式溢流阀), it can keep balance with inlet pressure directly; another is the pilot operated compound relief valve(先导式溢流阀), it can realize remote pressure regulation.
Pressure reducing valve: stabilize the outlet pressure.
It can be divided into three kinds: fixed pressure reducing valve(定值减压阀), fixed differential pressure reducing valve(定差减压阀) and fixed proportional pressure reducing valve(定比减压阀). They work as their their names.
03810Sequence valve: control the components action sequence of hydraulic system.
It can be divided into two kinds too, the directly operation type sequence valve, this kind is always used in low pressure system. The pilot operated compound sequence valve, it can be used in high pressure system.
The difference between the relief valve and the sequence valve:
1, the oil-out port of the relief valve is link to the oil tank, but the oil-out port of the sequence valve is link to another circuit;
2,the oil through the oil-out port of the relief valve is going into the oil tank, but the oil through the oil-out port of the sequence valve is oil with pressure, it need another leaking, then connect to the oil tank.
-889072390 Pressure switch: it is the component which can convert the pressure signal into electrical signal. It can make the hydraulic circuit more easy to measure and control.
Flow control valve: by changing the valve port area size of by changing the length of the duct to control the flow.
The working principle of the flow control: it mainly base on the principle of orifice discharge(小孔出流原理). It can be express as
C---- a coefficient , which is decided by the shape of the valve port, the flow state, character of the pressure oil and so on.
---- the area of the valve port.
---- the pressure difference of the two sides of the valve port.
m---- the coefficient of the flow control valve, always between 0.5 to 1, can be decided by experiment.
The flow control valve can be divided into two kinds, one is the throttle valve(节流阀), another is the flow speed control valve(调速阀).
The throttle valve always works with the relief valve. The flow stability is good for flow speed control valve. The flow speed control valve can not be used reverse. But the ordinary throttle valve can be used reverse.
Hydraulic basic circuit:
In this chapter, i mainly learned three types of hydraulic basic circuits, pressure control loop, speed control loop and directional control loop.
Pressure control loop:
There are pressure limited an adjustable pressure loop(限压和调压回路), relief loop(减压回路), booster loop(增压回路), unloading loop(卸荷回路), pressure holding circuit(保压回路) and balance circuit(平衡回路).
I mainly learned the adjustable pressure loop. For example,
The hydraulic cylinder is the actuator, which can transfer the hydraulic pressure into the mechanical motion.
The 2-positon 4-way direction control valve can change the direction of the flow , which can control the motion of the cylinder.
The ordinary throttle valve is for control the flow, which can control the speed of the motion of the cylinder.
The constant delivery hydraulic pump is for giving the oil a pressure to make it transmit power.
The relief valve can stabilize the inlet pressure and by adjust it , we can control the pressure of the circuit.
Speed control loop:
I mainly learned two types speed control loop, the throttling speed control loop adjusted by throttle valve(流量控制阀节流调速回路) and the variable output volume speed-adjust loop(flow control loop变排量容积调速).
There are three types of throttling speed control loop:
1, entrance throttling speed control loop(进口节流阀调速回路);
2, oil return throttling speed control loop (回油节流调速回路);
3,by-pass throttling speed control loop(旁路节流调速回路).
Entrance throttling speed control loop:
Throttle valve is on the inlet oil line, pump oil pressure is adjusted bye the relief valve.
AD: stepless speed regulation is reliable.
DIS: serious heat, low efficiency, the load is very small.
Oil return throttling speed control loop:
The throttle valve is on the outlet oil line, pump oil pressure is adjusted by the relief valve.
AD: it can bear negative load(the same direction of the movement). Cylinder has a back pressure, the air is not easy to go in, the movement is steady.
DIS: the pressure of the return oil chamber(回油腔) is too high,especially when it bear the negative load. Low efficiency.
By-pass throttling speed control loop:
The throttle valve is on the by-pas path. Part of the oil from the pump flow into the hydraulic cylinder pushing the piston(活塞). Another part of the oil through the throttle valve flowing back to the oil tank. The larger of the throttle valve’s port the slower of the cylinder. Now the relief valve is a safety valve.
AD: high efficiency, heavy load.
There are three types of variable output volume speed-adjust loop:
1, variable pump-constant displacement motor loop;
2,constant displacement pump-variable displacement motor loop;
3,variable pump-variable displacement motor loop.
Left is a constant displacement pump-variable displacement motor loop.
It has a electromagnetic change valve, a bidirectional variable displacement motor(双向变量液压马达) and a constant displacement pump.
Variable displacement pump-constant displacement motor loop:
It is a constant torque loop.
23749083820
Constant displacement pump-variable displacement motor loop:
This is a constant power loop.
Variable displacement pump-variable displacement motor loop:
This loop can adjust the speed in a wide range.
In the first stage, it is a variable pump-constant motor loop. In the second stage, it is a constant pump-variable motor loop.
Direction control loop:
I mainly learned direction charging loop with directional control valve.
This is a direction charging loop and it is also a adjustable pressure loop. There is a 2-position 4-way valve.
Pneumatic driving technique(气压传动技术):
Pneumatic transmission is using compressed as the working medium for energy transfer.
The working principle of pneumatic transmission:
It use the air compressor motor transfer the mechanical energy of motor into the air pressure, then under the action of control components, then the actuator transfer the air pressure to linear motion type or rotary motion type mechanical energy, then work for outside.
AD: low cost, high efficiency ,less pollution.
APP: it is widely used in wood-working machinery and light industrial machinery.
Basic structure:
1, energy element , such as air compressor motor, transfer the mechanical energy into air pressure;
2, control element, such as pressure valve, flow valve and direction valve, control the pressure, flow and direction of airflow;
3,processing element, such as air purifying device, remove the oil dust and dry the air;
4,actuator, such as air cylinder and air motor, transfer the air pressure into mechanical energy;
5,auxiliary element, used for elements’ connection, lubrication(润滑),noise limination, such as pipe joint, silencer, sensor and so on.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：液压与气压传动
无机及分析化学
核心内容
· 课程定位：无机及分析化学（Inorganic and Analytical Chemistry），生物科学专业基础课，内容分物质结构、四大平衡与滴定、溶液与胶体、热力学与动力学等模块。
· 物质结构
· 核外电子运动状态（电子云、量子数、原子轨道）
· 多电子原子核外电子排布（能量最低原理、洪特规则、泡利不相容原理）
· 元素周期律及元素性质的周期性变化（原子半径、电离能、电负性）
· 离子键（ionic bond）和共价键理论（covalent bond theory）
· 杂化轨道理论（hybrid orbital theory）：sp、sp²、sp³ 等杂化类型与分子构型
· 分子间力（van der Waals force、氢键 hydrogen bond）
· 分析化学概述
· 定量分析中的误差（系统误差、随机误差、准确度与精密度）
· 有效数字及运算规则（加减法按小数点后位数最少者，乘除法按有效数字最少者）
· 滴定分析法概述（titration）：标准溶液、指示剂、化学计量点与终点
· 四大平衡和滴定法
· 酸碱平衡（acid-base equilibrium）与酸碱滴定法
· 沉淀溶解平衡（precipitation-dissolution equilibrium，Ksp）与沉淀滴定法
· 配位平衡（complexation equilibrium，配位化合物 complex）与配位滴定法（EDTA 滴定）
· 氧化还原平衡（redox equilibrium）与氧化还原滴定法
· 分光光度法和电势分析法
· 分光光度法概述（spectrophotometry）
· 吸光度定律（Lambert-Beer law）：A = εbc，A 吸光度，ε 摩尔吸光系数，b 光程，c 浓度
· 显色反应（color reaction）
· 分光光度计测定方法
· 电势分析法基本原理（potentiometry）
· 离子选择性电极（ion-selective electrode，如 pH 玻璃电极）
· 溶液和胶体
· 溶液浓度表示方法：物质的量浓度、质量摩尔浓度、摩尔分数、质量分数等
· 稀溶液的依数性（common properties of the dilute solution）——只取决于溶质粒子数目，与溶质性质无关：
· 溶液的蒸气压下降（vapor pressure lowering）：一定温度下，难挥发性溶质使溶液蒸气压小于纯溶剂蒸气压；下降值与溶质粒子数目有关
· 溶液的沸点升高（boiling point elevation）：沸点（Boiling Point）为液体蒸气压等于外界压力时的温度；溶液沸点高于纯溶剂，浓度越大沸点越高
· 溶液的凝固点降低（freezing point depression）：凝固点（Freezing Point）为液相与固相蒸气压相等而平衡共存的温度；溶液凝固点低于纯溶剂，降低值只取决于溶液浓度而与溶质性质无关
· 渗透压（osmotic pressure）：渗透（osmosis）为溶剂通过半透膜向溶液一侧迁移；渗透压为使溶剂不发生渗透所需在溶液液面上施加的最小压力
· 胶体溶液
· 胶体（Colloid）：分散质粒子介于 1~100 nm（nanometer）之间的分散系
· 主要性质：丁达尔效应（Tyndall effect）——光束照射溶胶，从垂直入射光方向可观察到一条光亮的“通路”
· 化学热力学基础
· 热力学基本概念（系统、环境、状态函数、焓、熵、吉布斯自由能）
· 化学反应方向判断（ΔG < 0 自发）
· 化学热力学及热化学的计算（盖斯定律、标准生成焓）
· 化学反应速率和化学平衡
· 化学反应速率：研究单位时间内反应物或生成物浓度的变化；速率方程；反应速率理论（碰撞理论、过渡态理论）
· 化学平衡：一定条件下可逆反应正逆反应速率相等，各组分含量不变
· 化学平衡移动：平衡状态后反应条件改变，原平衡被破坏，各组分含量改变，在新条件下达到新平衡；勒夏特列原理（Le Chatelier's principle）
参考：来源：无极及分析化学.png｜专业：生物科学｜课程：无极及分析化学
专业英语（英文要点·大三大四）
核心内容
Basic concepts:
In this course, i mainly learned some specialized vocabularies. The lathe and its construction, the structure of the cutting tool and some knowledge about engineering materials.
Explanation of concepts:
Fixed action 固定作用 transverse feed横向进给 mainshaft rotating主轴转动
Longitudinal feed纵向进给 feed movement进给运功 tapping攻螺纹
Drill钻头， 钻孔 screw tap丝锥 turning kinetic车削运动 hand shank 手柄
Rotate speed control 转速控制
Lead screw：transform rotary motion into linear motion
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：专业英语
有机化学实验
核心内容
· 实验一：菠菜中提取天然色素 & 薄层色谱法（thin-layer chromatography, TLC）分离色素
· 实验原理
· 色素存在于菠菜叶绿体（chloroplast）中，研碎后释放。
· 利用各色素在层析液（developing solvent）中溶解度不同，随层析液在滤纸上扩散速度不同而实现分离。
· 实验步骤
· 称取 30 g 菠菜并研磨（mill）。
· 将菠菜放入小烧杯，加入 30 mL 配制好的乙醇（ethanol），盖上表面皿（watch glass）。
· 制备色谱柱（chromatographic column）：加入氧化铝（alumina）至 4/5 高度，再覆盖滤纸。
· 用纱布将烧杯中混合物挤入分液漏斗（separating funnel），加 10 mL 水洗涤。
· 将分液漏斗中溶液缓慢倒入色谱柱，滴加数滴丙酮（acetone）观察颜色变化。
· 易考点
· 色素分离的两大依据：溶解度差异 + 扩散速度差异。
· 氧化铝为固定相（stationary phase），乙醇/丙酮为流动相相关试剂。
· 关键数值：菠菜 30 g、乙醇 30 mL、水 10 mL、氧化铝填充至 4/5。
· 实验二：从茶叶中提取咖啡因（caffeine）
· 实验原理
· 咖啡因属生物碱（alkaloid），存在于茶叶、咖啡、可可等植物中。
· 茶叶中咖啡因质量分数约 1%~5%。
· 可通过升华法（sublimation）提取咖啡因。
· 实验步骤
· 称取 10 g 茶叶并研磨。
· 将茶叶装入滤纸制成的茶包（tea bag）。
· 将茶包放入索氏提取器（Soxhlet extractor）的提取管中。
· 向烧瓶中加入乙醇。
· 持续加热使溶剂沸腾，可见液体从提取管回流（reflux）至烧瓶。
· 多次回流后，取下索氏提取器。
· 蒸去过量乙醇。
· 将剩余液体倒入盛有数粒生石灰（quicklime）的蒸发皿（evaporating dish）中。
· 加热至粉末状。
· 制备一张布满小孔的滤纸。
· 将滤纸盖在蒸发皿上，放上漏斗，漏斗内放些纸巾。
· 加热混合物，咖啡因升华并附着在滤纸上。
· 易考点
· 咖啡因提取方法：升华法；茶叶中含量 1%~5%。
· 索氏提取器的作用：连续回流萃取（reflux extraction）。
· 生石灰（quicklime）的作用：吸水/干燥并中和，便于后续升华。
· 关键数值：茶叶 10 g。
· 升华现象：咖啡因附着于带孔滤纸上。
参考：来源：有机化学实验.png｜专业：生物科学｜课程：有机化学实验
有限元方法（英文要点·大三大四）
核心内容
Basic concepts:
In this course, i mainly learned about what is the finite element analysis, basis step of finite element analysis, some concepts about FEA and application of ANSYS. This course is mainly about knowing the concept and using in graduation design.
Explanation of concepts:
The concept of FEA:
FEA is an effective method to solve the problem of mathematics. The basic solution is to divide the computational domain(计算域) into a finite number of non overlapping units(不重叠的单元). In each unit, choose some suitable nodes as the interpolation points of the function(函数插值点), make the force acting on the unit is equivalent to acting on the node. The variables in the differential equations are rewritten into a linear expression of the values of the nodes and their derivatives, which are composed of the variables and their derivatives, are to use the binary function to approximate instead, by means of the variational principle or the weighted residual method, the differential equation is solved by the discrete method( HYPERLINK "https://www.baidu.com/s?wd=%E5%BE%AE%E5%88%86%E6%96%B9%E7%A8%8B&tn=44039180_cpr&fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1d9njcLPHK9PH6dPjRsPWTL0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGCpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3En1D3n1R1nW04" \t "http://zhidao.baidu.com/_blank" 微分方程中的变量改写成由各变量或其导数的节点值与所选用的插值函数组成的线性表达式，就是用叉值函数来近似代替 ，借助于 HYPERLINK "https://www.baidu.com/s?wd=%E5%8F%98%E5%88%86%E5%8E%9F%E7%90%86&tn=44039180_cpr&fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1d9njcLPHK9PH6dPjRsPWTL0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGCpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3En1D3n1R1nW04" \t "http://zhidao.baidu.com/_blank" 变分原理或加权余量法，将 HYPERLINK "https://www.baidu.com/s?wd=%E5%BE%AE%E5%88%86%E6%96%B9%E7%A8%8B&tn=44039180_cpr&fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1d9njcLPHK9PH6dPjRsPWTL0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGCpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3En1D3n1R1nW04" \t "http://zhidao.baidu.com/_blank" 微分方程离散求解).
Above is a very professional expression of the concept of FEA, as a matter of fact, in my opinion, it is cutting one whole workpiece into similar units, then calculate the force, stress and many other tings among them, through the results among the little units get the result of the whole workpiece. It is a special summation(累加法).
Basic step of FEA:
1, make the structure discretization, include element division, node number , unit number, node coordinate calculation, displacement constraint condition determination(将结构进行离散化，包括单元划分、结点编号、单元编号、结点坐标计算、位移约束条件确定).
2, calculation of equivalent nodal forces(等效节点力).
3,calculation of stiffness matrix(刚度矩阵first,calculate the stiffness unit by unit, then make them together into a stiffness matrix).
4,establish the integral equilibrium equation(建立平衡方程),introduce the constraint conditions(引入约束条件), and find out the nodal displacement(求解节点位移).
5,calculation of stress(应力计算).
Some relative concepts:
Any component with some function is called deformed body.
Movement caused by bearing force in any position on component is called displacement(位移).
The deformation state caused by bearing force in any position on component is called strain(应变).
The stress state cause by bearing force in any position on component is called stress(应力).
ANSYS:
ANSYS is famous in the world, can used for structural dynamics analysis, structural statics analysis, structural nonlinear analysis, thermal analysis, magnetic field analysis.
Basic step of stress and strain analysis of ANSYS:
1, create an analytical model of the 3D model.
2,define the material and various attributes(属性) of the model.
3,meshing.
4, define the reference plane.
5, choose the stress plane and add the load.
6,calculate and get the result.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：有限元方法
有机化学
核心内容
· 课程定位：有机化学（完整版）实验，内容分「理论部分（右主分支）」与「各论（左主分支）」两大板块，实验部分独立成支。
· 理论部分主干
· 基本理论
· 有机分子结构理论：共价键（covalent bond）及其属性、键的极性（bond polarity）
· 价键理论（valence bond theory, VB）
· 分子轨道理论（molecular orbital theory, MO）
· 杂化轨道理论（hybrid orbital theory）
· 烷烃与环烷烃（alkanes & cycloalkanes）
· 烯烃与二烯烃（alkenes & dienes）
· 立体化学（stereochemistry）
· 炔烃（alkynes）
· 芳香烃化合物（aromatic hydrocarbons）
· 卤代烃（halogenated hydrocarbons）
· 醇、酚、醚（alcohols, phenols, ethers）
· 醛、酮、醌（aldehydes, ketones, quinones）
· 各论主干
· 脂环烃（alicyclic hydrocarbons）
· 羧酸及其衍生物（carboxylic acids & derivatives）
· 含氮化合物（nitrogen-containing compounds）
· 生命有机化合物（bioorganic compounds）
· 波谱技术（spectroscopic techniques）
· 不被讨论内容（标注为不考/不讲授）
· 有机化学实验（见下）
· 各章核心考点（子节点展开）
· 烷烃和环烷烃：通性、命名、结构、同分异构、化学性质（取代 substitution、氧化 oxidation、裂解 cracking）
· 烯烃和二烯烃：结构、命名、同分异构、顺反异构（cis-trans isomerism）、加成（addition）、氧化、聚合（polymerization）；二烯烃分类、共轭（conjugation）、1,2-加成与1,4-加成
· 立体化学：同分异构、构型（configuration）、手性（chirality）、旋光异构（optical isomerism）、对映体（enantiomer）、非对映体（diastereomer）、外消旋体（racemate）、RS标记法（Cahn-Ingold-Prelog）
· 炔烃：命名、结构、加成、氧化、酸性、金属炔化物（metal acetylide）
· 芳香烃：分类、命名、苯的结构、休克尔规则（Hückel's rule）、定位效应（orientation effect）、亲电取代（electrophilic substitution：卤代 halogenation、硝化 nitration、磺化 sulfonation、Friedel-Crafts反应）
· 卤代烃：命名、分类、亲核取代（SN1/SN2）、消除（E1/E2）、札依采夫规则（Zaitsev's rule）
· 醇酚醚：醇的性质（与金属反应、酯化 esterification、脱水 dehydration、氧化）；酚的性质（酸性、FeCl₃显色、亲电取代）；醚的性质
· 醛酮醌：结构、命名、亲核加成（nucleophilic addition）、α-H反应（碘仿反应 iodoform reaction、羟醛缩合 aldol condensation）、氧化还原
· 羧酸及其衍生物：结构与性质、酸性、取代、脱羧（decarboxylation）；衍生物（酰卤 acyl halide、酸酐 anhydride、酯 ester、酰胺 amide）
· 含氮化合物：硝基化合物（nitro compounds）、胺类（amines：碱性强弱、与亚硝酸反应）、重氮化与偶合（diazotization & coupling）、重氮甲烷（diazomethane）
· 生命有机化合物：糖类（单糖 monosaccharide、双糖 disaccharide、多糖 polysaccharide）、氨基酸与蛋白质（amino acids & proteins）、脂类（lipids）、核酸（nucleic acids）
· 实验部分（重点）
· 从茶叶中提取咖啡因（caffeine extraction from tea leaves）
· 菠菜中提取天然色素 & 薄层色谱法分离色素（extraction of natural pigments from spinach & separation by thin-layer chromatography, TLC）
参考：来源：有机化学（完整版）-实验.png｜专业：生物科学｜课程：有机化学（完整版）-实验
先进制造技术（英文要点·大三大四）
核心内容
Basic concepts:
In this course, i mainly know about the modern design technology, advanced manufacturing technology, manufacturing automation technology, advanced manufacturing mode , their concepts and some related technology.
Explanation of concepts:
Modern design technology:
It is the technology which is using the new design concepts, design method and design tool to design. The most important of it is the CAD technology.
CAD includes:
1, using computer to carry out the product modeling, assembly, engineering drawing and the design of related documents;
2, product rendering, dynamic display, reliability design, kinematics and dynamics simulation and so on.
Characteristic of CAD:
1, emphasis on computer support and participation in design process.
2, emphasize the auxiliary function of the computer.
3, greatly reduce production costs.
4, labor saving.
Modern design method: optimum design, reliability design, value engineering,
green design.
Advanced manufacturing technology:
We mainly learned about the powder forging forming process(粉末锻造成型工艺), rapid prototyping manufacturing technology(快速原型制造技术) and special manufacturing technology(特殊制造技术).
Powder forging forming process:
It is a new technology which is combining the tradition powder metallurgy and forging. Combining the advantages of powder metallurgy and precision forging: low energy consumption, high material utilization, high precision forgings, good mechanical properties, high fatigue life.
Engineering process:
1,powder preparation, the powder must be with good mobility, less impurities.
2,make the powder molding with pressure, easy for fritting(烧结).
3,parision fritting(型坯烧结), high temperature fritting, increase the strength and density of the parision.
4,heat up before forging. 5, forging.
6, subsequent treatment, mostly surface treatment and heat treatment.
Rapid prototyping manufacturing technology:
It is a integrated technology combining CAD technology, numerical control technology, materials science, mechanical engineering, electronic technology , laser technology and other technology. And it is a integrated system technology can realize from parts design to the 3D entity prototype manufacturing. It includes:
1, SLA, stereolithoraphy apparatus(光敏液相固化成型).
2, LOM, laminated object manufacturing(选区片层凝结法).
3, SLS, selective laser sintering(选区激光烧结法).
(the detail is in 《Rapid Prototyping Manufacturing Technology》)
Special manufacturing technology:
1, laser manufacturing, high accuracy, no contact, almost any materials, high speed.
2, ultrasonic processing, can only process brittle materials.
3, water jet cutting process, use high speed water flow to cut materials, cheap, good for environment.
(the detail is in 《Precision and Special Processing Technology》)
Manufacturing automation technology:
Mainly includes CNC machine tool technology, industrial robot and flexible manufacturing system(FMS柔性制造系统).
FMS is a manufacturing automation system, which makes up by the number of CNC machining equipment, material holding equipment and computer control system. And it can be quickly adjusted according to the changes of manufacturing tasks or production varieties. So it can adapt to many varieties, small batch production.
Advanced manufacturing mode:
Concurrent engineering(CE):
CE is a kind of operating mode, which makes the process and production parallel and design integrated. This mode can make the product developers think about all the factors from product concept design to the demise of the product, almost the entire product life cycle, including quality, cost , schedule and user requirements at the beginning.
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：先进制造技术
植物生理学
核心内容
· 植物水分生理 (Water relations)
· 水分在植物生命活动中的作用：细胞质主要成分；参与代谢；作为溶剂；保持姿态（膨压）；调节温度
· 植物细胞对水分的吸收：渗透作用 (osmosis)；细胞的水势 (water potential, Ψw) 与渗透势 (osmotic potential, Ψs)
· 水势公式：Ψw = Ψs + Ψp + Ψm（Ψw 水势；Ψs 渗透势/溶质势；Ψp 压力势；Ψm 衬质势）
· 水分流动方向：由高水势→低水势
· 根系对水分的吸收：主动吸收与被动吸收；动力为根压 (root pressure) 与蒸腾拉力 (transpiration pull)
· 蒸腾作用 (transpiration)：水分从植物体表面（主要是叶片）以水蒸气状态散失到大气的过程；促进水分吸收与运输、降低叶温
· 蒸腾方式：气孔蒸腾 (stomatal transpiration)、角质层蒸腾 (cuticular transpiration)、皮孔蒸腾 (lenticular transpiration)
· 气孔蒸腾的调节（气孔开闭机制）
· 植物体内水分运输：导管 (vessel) 与管胞 (tracheid)
· 植物矿质营养 (Plant mineral nutrition)
· 植物必需的矿质元素：大量元素 (macroelements) 与微量元素 (microelements)
· 必需元素确定标准：Arnon 准则等
· 植物对矿质元素的吸收：根系吸收（主动运输、被动吸收）；根外营养（叶面施肥）
· 矿质元素的运输与利用
· 光合作用 (Photosynthesis)
· 概念：绿色植物利用光能，将 CO₂ 和 H₂O 转化为有机物并释放 O₂ 的过程
· 光合色素：叶绿素 (chlorophyll)、类胡萝卜素 (carotenoids)
· 过程：
· 光反应 (light reaction)：光系统Ⅰ/Ⅱ (PSⅠ/PSⅡ)、水的光解、ATP 与 NADPH 生成；光合磷酸化 (photophosphorylation)
· 暗反应 (dark reaction)/碳同化：C3 途径、C4 途径、CAM 途径
· 影响光合作用的因素：光照、CO₂ 浓度、温度、水分、矿质元素
· 植物生长物质（植物激素）
· 生长素 (auxin)：促进伸长生长、顶端优势 (apical dominance)、向性 (tropism)；作用具两重性
· 赤霉素 (gibberellin, GA)：促进茎伸长、种子萌发
· 细胞分裂素 (cytokinin, CTK)：促进细胞分裂、延缓衰老
· 脱落酸 (abscisic acid, ABA)：促进脱落、抑制生长、气孔关闭、抗逆
· 乙烯 (ethylene, ETH)：促进成熟、脱落、衰老
· 其他植物生长物质：油菜素甾醇 (brassinosteroids)、茉莉酸 (jasmonic acid)、水杨酸 (salicylic acid) 等
· 植物生长发育
· 种子萌发与休眠
· 植物的生长与分化
· 成花生理：光周期现象 (photoperiodism)、春化作用 (vernalization)、光敏色素 (phytochrome)
· 成熟、衰老与脱落
· 植物生殖生理
· 受精生理、果实与种子发育
· 参考教材：潘瑞炽《植物生理学》；Taiz & Zeiger《Plant Physiology》
参考：来源：植物生理学.png｜专业：生物科学｜课程：植物生理学
机器人技术基础（英文要点·大三大四）
核心内容
Basic concepts:
This course is an understanding course, we learned some information about robots in this course, such as history, application and so on.
Explanation of concepts:
We know that the most popular application of robot is the mechanical arms in factory, and we learned about how the mechanical arm know the position of the tool which is fixed at the end of the arm.
All the mechanical arms are made up of bars and joints, and the movements of them are realized by rotating the joints. So if we mount sensors at the joints to measure the rotation of them, we can know which direction and how much the joints rotation, and if we know the length of the bars, we can calculate die movements of the end of the mechanical arms. Then we can set a coordinate system to get the coordinate of the end of the mechanical arms in the space.
Then, my partners and i built a simple mechanical arm with the fischer, which is used for building robots like placing blocks. The arm can move things from one storage rack to another one. All the movements are controlled by the computer program which is saved in the single chip microcomputer.Then we write a paper about the mechanical arm. And we translate a paper from English into Chinese.
Cartesian coordinate robot(直角坐标机器人)：no rotate pair
Cylindrical coordinate robot(圆柱坐标机器人): one rotate pair
Spherical surface robot(求坐标机器人):two rotate pairs
Articulated robot(多关节机器人): more than 3 rotate pairs
参考：来源：大三大四专业课资料（英文.docx｜专业：机械工程｜课程：机器人技术基础
植物生理学实验
核心内容
· 一、气孔状态的观察及钾离子对气孔开度的影响
· 实验材料：蚕豆叶下表皮
· 定性观察方法
· 固定法：取蚕豆叶下表皮，迅速放入无水乙醇（absolute ethanol）中固定 2~3 min，取出后制片观察
· 印迹法：在蚕豆叶下表皮涂一层火棉胶（collodion），自然风干 2 min，取下膜片制成临时装片
· 定量测定
· 气孔密度测定：记录视野中的气孔数，取平均值
· 钾离子对气孔开度的影响
· 实验步骤：
· a) 取 3 个培养皿，分别加入 15 mL 5% KNO₃、0.5% KNO₃、蒸馏水（对照）
· b) 用镊子将蚕豆叶下表皮撕下，分别投入 3 个培养皿
· c) 将 3 个培养皿放入 25℃ 温箱中，保温 1.5 小时
· d) 各取出表皮置于人工光照条件下，用 40W 灯照 10 min
· e) 在显微镜下观察气孔的开度
· 易考点：K⁺ 浓度梯度对气孔开度的影响（高浓度 KNO₃ 促进气孔开放）；蒸馏水为对照；温度 25℃、光照 40W/10min 为标准化条件
· 二、植物组织含水量测定
· 原理：水遇热蒸发为水蒸气，用烘干法（oven-drying method）测定植物组织中的含水量
· 步骤：
· 1. 用打孔器分别在新鲜黄瓜和洋葱的里脊部位切取约 30 片，放入称量瓶并称重（W1，Wf）
· 2. 烘干：放入烘箱中，105℃，烘干若干小时
· 3. 称重计算：称干重（W2，Wf2）
· 组织含水量 = (W1 − W2) / …（公式部分字迹不清）
· 干旱/相对含水量计算（公式部分字迹不清）
· 关键数值：烘干温度 105℃；取样量约 30 片；材料为黄瓜和洋葱里脊部位
· 易考点：W1 为鲜重（fresh weight），W2 为干重（dry weight）；含水量计算基于鲜重与干重之差
· 三、左侧注释
· 含"定量""定性"说明与公式（内容字迹不清，无法提取）
参考：来源：植物生理学实验.png｜专业：生物科学｜课程：植物生理学实验