教学课件:《大学化学(1).ppt

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1、 大学化学大学化学(1)医学基础化学医学基础化学CHAPTER 1 Solution (4h)2 Electrolyte solution(5h)3 Buffer solution(4h)5 Rates of chemical reaction(4h)10 Titrimetry(4h)11 Spectropotometry(2h)6 Electrochemistry(6h)12 The colloidal system and surface phenomena(5h)7 Atomic Structure(4h)8 Molecular Structure(4h)9 Coordination C

2、ompounds(6h)课本课本(英文、中文(英文、中文 共共48-5248-52学时)学时)顺序顺序 先中文,再英文先中文,再英文;记忆英文的词汇和相关定义记忆英文的词汇和相关定义 正确理解基本概念、基本原理及正确理解基本概念、基本原理及适用范围适用范围 抽象抽象联系实际,勤思考,理解,推理联系实际,勤思考,理解,推理。预习自学预习自学 记笔记,及时复习、消化、答疑记笔记,及时复习、消化、答疑。重视作业重视作业 适当做习题适当做习题。小论文:小论文:医学中的化学问题医学中的化学问题(调查论述)(调查论述)学习方法:学习方法:CHAPTER 1 Solution (4h)2 Electroly

3、te solution(5h)3 Buffer solution(4h)5 Rates of chemical reaction(4h)10 Titrimetry(4h)11 Spectropotometry(2h)6 Electrochemistry(6h)12 The colloidal system and surface phenomena(5h)7 Atomic Structure(4h)8 Molecular Structure(4h)9 Coordination Compounds(6h)溶液化学溶液化学化学动力学化学动力学分析化学分析化学电化学电化学胶体化学胶体化学结构化学结构

4、化学【调查医院中化学知 识的运用】1 分学习小 组(选出小组长)2 利用课余时间分头到图 书馆、网 上查找资料 3 到医院实地考察、调查、验证 4 总结 教学时间教学时间 :可利用课余时间查找资料,医院考察 每小组写出一份调查报告,堂课总结。调查提纲调查提纲 :查找化学在医学上运用:诊断、治疗、预防等医学成果研究 对资料归类进入学校网络课堂:山东大学山东大学 校部机关校部机关 本科生院本科生院 网络学堂网络学堂 山东大学课程中心山东大学课程中心 http:/ 课程网站点击排行课程网站点击排行更多更多 医学基础化学医学基础化学刘洛生刘洛生 医学理化实验医学理化实验赵全芹赵全芹 分组分组 地点地点

5、 1组组 7202 2组组 7216 3组组 7217医学基础化学实验(医学基础化学实验(1)山东大学山东大学 学院总览学院总览 化学院化工学院化学院化工学院 示范中心示范中心 无机及分析化学实验无机及分析化学实验 网络资源网络资源 (多种形式多种形式)基础化学实验操作内容简介(观看一、五、六、七)基础化学实验操作内容简介(观看一、五、六、七)实验实验1 1内容:内容:实验基本操作、实验基本操作、酸碱标准溶液的配制与标定(实验十六)酸碱标准溶液的配制与标定(实验十六)网络教学:网络教学:实验循环实验循环1 实验一实验一 粗食盐精制粗食盐精制 (72027202)实验九实验九 醋酸电离平衡常数的

6、测定醋酸电离平衡常数的测定(72167216)实验三、实验三、十七十七 分析天平的使用分析天平的使用 硼砂含量测定硼砂含量测定 (72177217)基础化学实验操作内容简介基础化学实验操作内容简介 观看(二、三、四、八、九)观看(二、三、四、八、九)网络教学:网络教学:进入方法:进入方法:山东大学山东大学 学院总览学院总览 化学院化工学院化学院化工学院 示范中心示范中心 无机及分析化学实验无机及分析化学实验 网络资源网络资源(多种形式多种形式)医学基础化学实验(医学基础化学实验(1)考核方法考核方法 采取平时和期终两种考核相结合方法采取平时和期终两种考核相结合方法:1.平时考核:平时考核:出勤

7、情况、实验预习、实验过程、实验操作、出勤情况、实验预习、实验过程、实验操作、实验报告、实验安全卫生等。实验报告、实验安全卫生等。2.期终考核:期终考核:考核学生的基本操作技能或多种形式。考核学生的基本操作技能或多种形式。(涵盖所有实验内容的相关技能操作)(涵盖所有实验内容的相关技能操作)平时成绩占平时成绩占70、期终成绩占期终成绩占30。CHAPTER ONE SOLUTION1-1 Basic Terms of Solution1-2 Solubility of Solution1-3 Solution Concentration1-4 Colligative Properties of S

8、olutions问题:生理盐水?生理盐水?等渗溶液?等渗溶液?溶液浓度、稀溶液的依数性、渗透及渗透压概念有关溶液浓度、稀溶液的依数性、渗透及渗透压概念有关(5%GS、50%GS)(0.9%NaCl)肾脏衰竭的治疗方法肾脏衰竭的治疗方法血液透析原理?血液透析原理?为什么临床输液要注意所输入溶液的浓度和体积呢?为什么临床输液要注意所输入溶液的浓度和体积呢?生物膜与疾病生物膜与疾病1-1 Basic Terms of Solution A solution is a homogeneous mixture of two or more substances evenly distributed in

9、 each other.When one of these substances is a liquid and the others are so1ids or gases,we tend to think of the liquid as the substance that dissolves the solid or gas.The liquid is referred to as the solvent and the solids and gases as the solutes.Such interactions between solute and solvent molecu

10、les is known as solvation(溶剂化溶剂化).When the solvent is water it is known as hydration.(水合)(水合)2.Molarity(c):moles solute/Liter solution 3.Molality*(mB):moles solute/Kg solvent 4.Mole Fraction(x):1-3 Solution Concentration 1.Amount-of-substance Concentration c(物质的量浓度)(物质的量浓度)(体积摩尔浓度)(体积摩尔浓度)(质量摩尔浓度)(质

11、量摩尔浓度)(摩尔分数)(摩尔分数)1.Amount-of-substance Concentration is a concentration unit equal to the amount-of-substance of solute dissolved in a liter of solution nB(mol)or cB=(mol/L)V(L)eg:58.5 g of NaCl is dissolved in enough water to give 1L of solution,what is the Amount-of-substance Concentration of the

12、 solution?Answer:cNaCl=1mol/L 2.Molarity(c):_moles solute/Liter solution nB cB=V Molarity(c):Amount-of-substance ConcentrationEg:If 0.435 g of KMnO4 is dissolved in enough water to give 250.mL of solution,what is the molarity of KMnO4?Solve:the first step is to convert the mass of material to moles.

13、0.435 g KMnO4 1 mol KMnO4 =0.00275 mol KMnO4 158.0 g KMnO4Molarity KMnO4=0.00275 mol KMnO4 =0.0110mol/L 0.250 L solution3.Molality _moles solute/kg solvent Molality is a concentration unit equal to the amount-of-substance of solute dissolved in a kilogram of solvent.amount-of-substance of solute(nB)

14、Molality(mB)=mass of solvent(mA)nB or mB=mA 若将58.5gNaCl溶于1kg水,所得溶液的质量摩尔浓度是1 mo1/kg4 Mole fraction (Amount-of-substance Fraction)Moles of A(Amount-of-substance of A)Mole fraction of A=Sum of moles of all components(组分)or nA xA=nA+nB+它表示某物质的它表示某物质的 物质的量与混合物的总物质的量之比,物质的量与混合物的总物质的量之比,常以符号常以符号“x”表示,它没有单位

15、。表示,它没有单位。Alcohol solution nH2O =2molnalcohol =3mol nH2Ox H2O =nalcohol+nH2O =2/(2+3)=0.4Solutions By“Parts”Parts per million is the number of particles of solute per one-million particles of solution.1 ppm=1 mg/L (10-3)Parts per billion(十亿)十亿)is the number of particles of solute per one-billion par

16、ticles of solution.1 ppb=1 g/L(10-6)Parts per trillion(万亿)万亿)is the number of particles of solute per one-trillion particles of solution.1 ppt=1 ng/L(10-9)等物质的量的反应规则等物质的量的反应规则 关于浓度,细读中文书关于浓度,细读中文书 p8-10aA+tTdD+eE)()()()(eEndDntTnaAn1-4 Colligative Properties of Solutions 1 Vapor Pressure Lowering 2

17、Boiling Point Elevation 3 Freezing Point Depression 4 Osmosis and Osmotic Pressure 5 The Colligative Properties of Electrolyte Solution 6 Isotonic(等),Hypotonic(低),Hypertonic(高)The first depends on the nature of solute eg.Color、electric and the volume changeThe second not depend on the nature of solu

18、te eg.vapor pressure、boiling point、freezing point and osmotic pressure1-4 Colligative Properties of SolutionsTwo kinds of properties of a solution:colligative property:All these properties depend on the collective effect of the number of dissolved particles rather than on the nature of the particles

19、 involved 依数性依数性 指溶液的某些性质与溶质的粒子数的多少有关,与溶质本性无关。通性通性(1)the lowering of the vapor pressure of the solution relative to that of the pure solvent,(2)the elevation of the boiling point,(3)the depression of the freezing point,(4)the phenomenon of osmotic pressure.colligative property nonvolatile,nonelectro

20、lyte dilute solution依数性依数性 难挥发性难挥发性 非电解质非电解质 稀溶液稀溶液 Evaporation is the process by which water is converted from its liquid form to its vapor form.1-4.1 Lowering of Vapor PressureEvaporation is a surface phenomenon-some molecules have enough kinetic energy to escape.蒸发的蒸发的2个条件:个条件:质点的动能足够大;质点的动能足够大;运

21、动的方向指向液体表面运动的方向指向液体表面Condensation is the change of water from its gaseous form(water vapor)into liquid water.If the container is closed,an equilibrium is reached where an equal number of molecules return to the surface.Saturated Vapor PressureEquilibrium:rate evaporation=rate condensation.At this po

22、int the vapor is said to be saturated,and the pressure of that vapor is called the saturated vapor pressure.The pressure of this equilibrium is called the vapor pressure.Lowering of Vapor Pressure(a)vapor pressure of pure solvent (b)vapor pressure of solutionpo pp=po-p A dilute solution:Vapor pressu

23、re(p)of is directly proportional to mole fraction of the solvent.p xA xA is mole of solvent The constant is the vapor pressure of pure solvent p p=pxA (经验公式)经验公式)比例系比例系数数 xA+xB=1 p=po xA =po(1-xB)=po-po xB po-p=po xB p=po xB Raoults law:Vapor pressure lowing(p)of a dilute solution that containing no

24、nvolatile,nonelectrolyte is directly proportional to the amount-of-substance fraction of the solute and has nothing to do with the nature of solute.Raoults law在一定温度下,难挥发在一定温度下,难挥发非电解质稀溶液蒸气压非电解质稀溶液蒸气压下降下降p p与溶质的质量与溶质的质量摩尔分数摩尔分数x xB B成正比,而成正比,而与溶质的本性无关与溶质的本性无关 For a dilute solution nA nB,(nA+nBnA)p=K

25、bB (1-9)ABBABBnnnnnxAAMgn1000BABnMpxpp1000Suppose:solvent is 1000g p=K bB mBmB若以水为溶剂,若以水为溶剂,1kgH2O中含有中含有nB在数值上在数值上mBnB Raoults law:Vapor pressure lowing of a dilute solution that containing nonvolatile,nonelectrolyte is directly proportional to the molality of the solution and has nothing to do with

26、 the nature of solute.p=K K mBRaoults law:在一定温度下,难挥发非电解质稀溶液蒸气在一定温度下,难挥发非电解质稀溶液蒸气压下降压下降p与溶液的质量摩尔浓度与溶液的质量摩尔浓度mB成正比,而与溶质的本成正比,而与溶质的本性无关性无关。Raoults law:p=K mBT(温度)p pure solventsolutionsolutionFigure 1-1 The vapor pressure of solution稀溶液的稀溶液的mB大,大,粒子数目越多,溶液的粒子数目越多,溶液的p越低,越低,p 越大。越大。Vapor Pressure Loweri

27、ng Describe what is happening in the pictures below.Use the concept of vapor pressure lowering to explain this phenomenon.1-4.2 Elevation of Boiling PointWhy?anti-freeze(防冻剂)防冻剂)(or salt)?汽车散热器中的汽车散热器中的溶液作用溶液作用 保护发动机保护发动机冬季免于冰冻冬季免于冰冻 夏季免于高温夏季免于高温increasing the boiling point Figure 1-2 The vapor pres

28、sure of solution is lowerBoiling Point Elevation Tb=(Tb-Tb)Tb_ b.p.of pure solvent Tb _ b.p.solvent in solution Tb=Kb mBKb is different for different solvent大量的实验得出大量的实验得出溶液的沸点升高与质量摩尔浓度有如下关系溶液的沸点升高与质量摩尔浓度有如下关系Kb为溶剂的摩尔沸点升高常数为溶剂的摩尔沸点升高常数 Table 1-1 Boiling-Point elevation and Freezing-Paint Depression

29、Constants Solvent Formula Tb()Kb Tf()KfAcetic acid CH3COOH 118.1 3.07 17 3.9Benzene C6H6 80.1 2.53 5.5 4.9Carbon tetrachloride CCl4 76.7 5.03 -22.9 32Diethyl ether C4H 10O 34.7 2.02 -116.2 1.8Ethanol C2H5OH 78.4 1.22 -114.7 -Naphthalene C10H8 -80.5 6.8Water H2O 100.0 0.512 0.0 1.86萘萘二乙醚1-4.3 Depress

30、ion of Freezing Point Freezing Point:-Temperature at which a liquid congeals(凝固)into the solid state at a given pressure.凝固点凝固点 是溶剂的固相与液相是溶剂的固相与液相平衡共存平衡共存的的温度温度 Water 0 0C P固相固相=P液相液相(固(固-液两相共存)液两相共存)0 0C以上以上 P固相固相 P液相液相 (冰溶化)(冰溶化)0 0C以下以下 P固相固相 P液相液相 (水转化为冰)(水转化为冰)Freeze piont:H2O solution:0 P溶液溶液

31、P冰冰 (冰吸收热量融化,使体系温度降低)(冰吸收热量融化,使体系温度降低)Figure 1-2 The vapor pressure of solution is lower0.610ab Tf=Kf mBKf is the molal freezing point depression constant of the solvent.Kf is different for different solvent Tf=(Tf-Tf)Tf_ f.p.of pure solvent Tf _ f.p.solvent in solution Depression of Freezing Point

32、Tf Table 1-1 Boiling-Point elevation and Freezing-Paint Depression Constants Solvent Formula Tb()Kb Tf()KfAcetic acid CH3COOH 118.1 3.07 17 3.9Benzene C6H6 80.1 2.53 5.5 4.9Carbon tetrachloride CCl4 76.7 5.03 -22.9 32Diethyl ether C4H 10O 34.7 2.02 -116.2 1.8Ethanol C2H5OH 78.4 1.22 -114.7 -Naphthal

33、ene C10H8 -80.5 6.8Water H2O 100.0 0.512 0.0 1.86萘萘二乙醚 例例 取取0.749g0.749g谷氨酸溶于谷氨酸溶于50.0g50.0g水,测得水,测得凝固点凝固点为为 0.1880.188,试求谷氨酸的摩尔质量。,试求谷氨酸的摩尔质量。解:利用公式,解:利用公式,TTf f K Kf fmmB B 所以所以 M M148148(gmolgmol1 1)按谷氨酸的分子式按谷氨酸的分子式COOHCHNHCOOHCHNH2 2(CH(CH2 2)2 2COOHCOOH计算,计算,其摩尔质量应为其摩尔质量应为147 gmol147 gmol1 1。De

34、termining Molecular Weight (p21)0.501000749.086.1188.0M 例例1-9 1-9 乙二醇乙二醇CHCH2 2(OH)CH(OH)CH2 2(OH)(OH)是一种常用的汽车防冻剂,它溶于水并是一种常用的汽车防冻剂,它溶于水并完全是非挥发性的(完全是非挥发性的(b.p.197b.p.197)。)。计算在计算在2505g2505g水中溶解水中溶解651g651g该物质的溶液的凝固点。该物质的溶液的凝固点。夏天能否将它夏天能否将它用于汽车散热器中?用于汽车散热器中?乙二醇的摩尔质量是乙二醇的摩尔质量是62.01g/mol62.01g/mol。解:溶液的

35、质量摩尔浓度解:溶液的质量摩尔浓度kgmolmB/19.42505100001.62651 Tf KfmB1.864.197.79(K)因为纯水的凝固点是因为纯水的凝固点是273K,该溶液凝固点该溶液凝固点 Tf 273-7.79 265.21K 沸点升高沸点升高 Tb 0.524.192.2(K)此溶液在此溶液在375.2K沸腾,所以夏天它能用于汽车散热器中防止溶沸腾,所以夏天它能用于汽车散热器中防止溶液沸腾。液沸腾。Determining Molecular Weight (p21)Dissolves 2.06 g of an unknown solid substance in 164

36、g of cyclohexane(C6H12环己烷)and determines that the freezing point of this solution is 4.76.The freezing point of pure cyclohexane is 6.47;the Kf is 20.0K kg/mol.What is the molecular weight of the unknown solid,(Assume that it is nonionizable and nonvolatile.)Solution:The freezing-point depression is

37、Tf=freezing point of pure solvent-freezing point of solution =6.47-4.76=1.71 according to according to Tf=Kf mB mB=Tf/Kf=1.71/20.0=0.0855 (mol/kg)Amount-of-substance of solute (nB)=0.164kg0.0855 mol/kg =0.0140 mol n n=m m/M/M Molar mass unknown=2.06g/0.0140mol=147 g/mol 1-4.4 Osmotic Pressure Osmosi

38、s is the spontaneous movement(自发运动自发运动)of water across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration渗透达平衡:渗透达平衡:溶液与纯溶剂之间产生溶液与纯溶剂之间产生压力差压力差 :由于溶剂渗透造成的,所以将其称为由于溶剂渗透造成的,所以将其称为渗透压。渗透压。:维持渗透平衡所向溶液上方施加的最小压力。维持渗透平衡所向溶液上方施加的最小压力。单位是单位是Pa或或kPa。实验证明

39、:实验证明:在一定在一定温度温度下,下,与它的浓度成正比;与它的浓度成正比;在一定在一定浓度浓度时,时,与绝对温度成正比。与绝对温度成正比。1886年荷兰物理化学家范托夫(年荷兰物理化学家范托夫(vant Hoff)综合上述实综合上述实验结果,指出稀溶液的渗透压与温度、浓度的关系同验结果,指出稀溶液的渗透压与温度、浓度的关系同理想气态方程一致理想气态方程一致:V nRT cRT For a dilute solution,公式的意义在于:一定温度下,溶液的渗透压与溶液公式的意义在于:一定温度下,溶液的渗透压与溶液 的质量摩尔浓度成正比,也就是说的质量摩尔浓度成正比,也就是说:与溶液中所含溶质质

40、点的数目成正比,而与溶质的本与溶液中所含溶质质点的数目成正比,而与溶质的本性无关。性无关。cRT mBRT 难挥发非电解质稀溶液依数性总结难挥发非电解质稀溶液依数性总结 p =K K mB Tb =Kb mB Kb=0.512Tf =Kf mB Kf=1.86 =RT mB Problem1.What would the boiling point of a solution be if 18.0g of glucose were dissolved on 1000g of H2O?freezing point?Osmotic Pressure?2.What would the boiling

41、 point of a solution be if 5.85g of NaCl were dissolved on 1000g of H2O?1.解解 Tb =Kb mB =0.520.10=0.052 T b=100+0.052 =100.0521-4.5 The Colligative Properties of Electrolyte Solution p=i K K mB Tb=i Kb mB Tf =i Kf mB i-Vant Hoff factor =i RT mB For glucose i=1;for KNO3 i=2;for MgCl2,i=31-4.6 Isotonic

42、,Hypotonic,Hypertonic SolutionOsmosis is important in many biological processesA cell might be thought of as an aqueous solution surrounded by a semipermeable membrane.The solutions surrounding cells must have the same osmotic pressure.Otherwise,water will either leave the cell,dehydrating(脱水脱水)it,o

43、r enter the cell,causing it to burst(溶胀溶胀)hemolysis(溶血)溶血).Osmosis and Blood Cells(a)A cell placed in an isotonic solution.The net movement of water in and out of the cell is zero because the concentration of solutes inside and outside the cell is the same.(5%C6H12O6)(b)In a hypertonic solution,the

44、concentration of solutes outside the cell is greater than that inside.There is a net flow of water out of the cell,causing the cell to dehydrate,shrink,and perhaps die.(50%C6H12O6)(c)In a hypotonic solution,the concentration of solutes outside of the cell is less than that inside.There is a net flow

45、 of water into the cell,causing the cell to swell and perhaps to burst.(1%C6H12O6)IsotonicIsotonicHypertonicHypertonicHypotonicHypotonic水、电解质紊乱水、电解质紊乱1-4.7 Osmolarity(渗透物质的量浓度)Osmolarity c cosos (mol/L or mmol/L).is the measure of solute concentration,defined as the number of osmoles(Osm)of solute p

46、er liter of solution渗量浓度渗量浓度cos _指指1L溶液中能产生渗透效应的各种溶液中能产生渗透效应的各种 溶质微粒(分子或离子)的总物质的量。溶质微粒(分子或离子)的总物质的量。例例 计算医院补液用的计算医院补液用的50.0 gL-1葡萄糖溶液和葡萄糖溶液和9.00 gL-1 NaCl溶液溶液(生理盐水生理盐水)的的cos.解解 葡萄糖的摩尔质量葡萄糖的摩尔质量M=180 gM=180 gmolmol-1-1,50.0 g50.0 gL L-1-1C C6 6H H1212O O6 6 溶液的渗量浓度溶液的渗量浓度为:为:111osLmmol2781mol1000mmol

47、mol180gL50.0gcNaClNaCl的摩尔质量的摩尔质量M=58.5 gM=58.5 gmolmol-1-1,9.00 g9.00 gL L-1-1 NaClNaCl溶液的溶液的渗渗量量浓度为浓度为:111osL308mmol21mol1000mmolmol58.5gL9.00gcBody fluids:280-320 mmol/LBody fluids:?For dilute solutions,osmolarity is expressed in milliosmols per liter(m Osm/L).What is the osmolarity of a 0.9%NaCl

48、solution?osmolarity=molarity i 1000 =0.9%-2=0.308 Osm/L 100M(58.5)(308mOsm/L)What is the osmolarity of a 5%glucose solution?Solution:Glucose is a nonelectrolyte;number of particlesosmolarity=molarity-=molarity i molecule of solute 1000 =5%-1=0.277 Osm/L 100M(180)=277mOsm/L Edema(水肿)occur1-4.8 Crysta

49、lloid Osmotic Pressure and Colloidal Osmotic Pressure1-4.8 Crystalloid Osmotic Pressure and Colloidal Osmotic Pressure Crystalloid Osmotic Pressure(772KPa)by NaCl,NaHCO3,regulate(调节)balance of fluid and electrolyte on the two side of cell wall Colloidal Osmotic Pressure(2.934.00KPa)by large molecula

50、r(Protein)regulate balance of fluid and electrolyte on the two side of blood capillary wall.(IC FIC F)(E C FE C F)(In te rs titia l flu idIn te rs titia l flu id)(PlasmaPlasma)水、电 解 质 紊 乱水、电 解 质 紊 乱Crystalloid Osmotic PressurColloidal Osmotic Pressure?Crystalloid Osmotic Pressure If lack of water in

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