The technique of coupling two loudspeakers to obtain a signal proportional to the velocity of the cone is known. The sound at a distant point from a loudspeaker is related to the diaphragm displacement. Since the indu...The technique of coupling two loudspeakers to obtain a signal proportional to the velocity of the cone is known. The sound at a distant point from a loudspeaker is related to the diaphragm displacement. Since the induced e.m.f is proportional to the voice coil velocity,measurement of induced e.m.f enables us to obtain the displacement of the cone and hence we can plot the SPL curve for a loudspeaker. This method has some limitations in that it is particularly applicable only when one is interested in using the output of the second speaker used as a sensor in some further applications.展开更多
Values of the second thermodynamic dissociation constant pK2 of the protonated form of monosodium 1,4-piperazinediethanesulfonate (PIPES) have been determined at twelve different temperatures in the temperature range ...Values of the second thermodynamic dissociation constant pK2 of the protonated form of monosodium 1,4-piperazinediethanesulfonate (PIPES) have been determined at twelve different temperatures in the temperature range from (278.15 to 328.15) K including the body temperature 310.15 K by measurement of the electromotive-force for cells without liquid junction of the type: Pt (s), H2 (g), 101.325 kPa|Na-PIPES (m1) + Na 2-PIPES (m2) + NaCl (m3)|AgCl (s), Ag (s), where m1, m2 and m3 indicate the molalities of the corresponding species at 1 atm = 101.325 kPa in SI units. The pK2 values for the dissociation of Na-PIPES are represented by the equation: pK2 = -1303.76/T + 48.369 - 6.46889 lnT with an uncertainty of ± 0.001. The values of pK2 for Na-PIPES were found to be 7.1399 ± 0.0004 at 298.15 K and 7.0512 ± 0.0004 at 310.15 K, respectively, and indicate that this buffer would be useful as pH standard in the range of physiological application. Standard thermodynamic quantities for the acidic dissociation process of Na-PIPES have been derived from the temperature coefficients of the pK2. These values are compared with those of structurally related N-substituted PIPERAZINE and TAURINE at 298.15 K.展开更多
The Low Frequency Synchromotor Drive Mine Hoist System fed by the cycloinverter has good features from the technological and economical point of view. According to the erating char acteristic of the mine hoist system,...The Low Frequency Synchromotor Drive Mine Hoist System fed by the cycloinverter has good features from the technological and economical point of view. According to the erating char acteristic of the mine hoist system, an advanced analysis is given to the construction, the operating characteristics and the harmonics of the magnetomotive force of the synchromotor fed by the cy cloinverter, and the beneficial suggestions are also given in this paper.展开更多
Chloroplasts are central to solar light harvesting and photosynthesis. Optimal chloroplast functioning is vitally dependent on a very intensive traffic of metabolites and ions between the cytosol and stroma, and shoul...Chloroplasts are central to solar light harvesting and photosynthesis. Optimal chloroplast functioning is vitally dependent on a very intensive traffic of metabolites and ions between the cytosol and stroma, and should be attuned for adverse environmental conditions. This is achieved by an orchestrated regulation of a variety of transport systems located at chloroplast membranes such as porines, solute channels, ion-specific cation and anion channels, and various primary and secondary active transport systems. In this review we describe the molecular nature and functional properties of the inner and outer envelope and thylakoid membrane channels and transporters. We then discuss how their orchestrated regulation affects thylakoid structure, electron transport and excitation energy transfer, proton-motive force partition, ion homeostasis, stromal pH regulation, andvolume regulation. We link the activity of key cation and anion transport systems with stress-specific signaling processes in chloroplasts, and discuss how these signals interact with the signals generated in other organelles to optimize the cell performance, with a special emphasis on Ca^2＋ and reactive oxygen species signaling.展开更多
为了解东方田鼠(Microtusfortis)筑巢行为在不同环境条件下的适应性进化。在实验室内采用48 h等级法和连续144 h巢材获取重量法,比较了东方田鼠长江亚种(M. f. calamorumt)和指名亚种(M. f. fortis)筑巢行为。结果表明,东方田鼠指名亚...为了解东方田鼠(Microtusfortis)筑巢行为在不同环境条件下的适应性进化。在实验室内采用48 h等级法和连续144 h巢材获取重量法,比较了东方田鼠长江亚种(M. f. calamorumt)和指名亚种(M. f. fortis)筑巢行为。结果表明,东方田鼠指名亚种和长江亚种皆能主动获取巢材并建筑质量良好的巢,具有稳定的筑巢行为;东方田鼠两个亚种的筑巢行为在利用巢材能力(P <0.01)和获取巢材能力(P <0.05)上皆具有显著性差异;指名亚种雌雄个体在利用巢材(P <0.05)和获取巢材的能力(P<0.05)上皆具有显著差异,而长江亚种在这两个方面都不存在性别差异。展开更多
文摘The technique of coupling two loudspeakers to obtain a signal proportional to the velocity of the cone is known. The sound at a distant point from a loudspeaker is related to the diaphragm displacement. Since the induced e.m.f is proportional to the voice coil velocity,measurement of induced e.m.f enables us to obtain the displacement of the cone and hence we can plot the SPL curve for a loudspeaker. This method has some limitations in that it is particularly applicable only when one is interested in using the output of the second speaker used as a sensor in some further applications.
文摘Values of the second thermodynamic dissociation constant pK2 of the protonated form of monosodium 1,4-piperazinediethanesulfonate (PIPES) have been determined at twelve different temperatures in the temperature range from (278.15 to 328.15) K including the body temperature 310.15 K by measurement of the electromotive-force for cells without liquid junction of the type: Pt (s), H2 (g), 101.325 kPa|Na-PIPES (m1) + Na 2-PIPES (m2) + NaCl (m3)|AgCl (s), Ag (s), where m1, m2 and m3 indicate the molalities of the corresponding species at 1 atm = 101.325 kPa in SI units. The pK2 values for the dissociation of Na-PIPES are represented by the equation: pK2 = -1303.76/T + 48.369 - 6.46889 lnT with an uncertainty of ± 0.001. The values of pK2 for Na-PIPES were found to be 7.1399 ± 0.0004 at 298.15 K and 7.0512 ± 0.0004 at 310.15 K, respectively, and indicate that this buffer would be useful as pH standard in the range of physiological application. Standard thermodynamic quantities for the acidic dissociation process of Na-PIPES have been derived from the temperature coefficients of the pK2. These values are compared with those of structurally related N-substituted PIPERAZINE and TAURINE at 298.15 K.
文摘The Low Frequency Synchromotor Drive Mine Hoist System fed by the cycloinverter has good features from the technological and economical point of view. According to the erating char acteristic of the mine hoist system, an advanced analysis is given to the construction, the operating characteristics and the harmonics of the magnetomotive force of the synchromotor fed by the cy cloinverter, and the beneficial suggestions are also given in this paper.
文摘Chloroplasts are central to solar light harvesting and photosynthesis. Optimal chloroplast functioning is vitally dependent on a very intensive traffic of metabolites and ions between the cytosol and stroma, and should be attuned for adverse environmental conditions. This is achieved by an orchestrated regulation of a variety of transport systems located at chloroplast membranes such as porines, solute channels, ion-specific cation and anion channels, and various primary and secondary active transport systems. In this review we describe the molecular nature and functional properties of the inner and outer envelope and thylakoid membrane channels and transporters. We then discuss how their orchestrated regulation affects thylakoid structure, electron transport and excitation energy transfer, proton-motive force partition, ion homeostasis, stromal pH regulation, andvolume regulation. We link the activity of key cation and anion transport systems with stress-specific signaling processes in chloroplasts, and discuss how these signals interact with the signals generated in other organelles to optimize the cell performance, with a special emphasis on Ca^2＋ and reactive oxygen species signaling.
文摘为了解东方田鼠(Microtusfortis)筑巢行为在不同环境条件下的适应性进化。在实验室内采用48 h等级法和连续144 h巢材获取重量法,比较了东方田鼠长江亚种(M. f. calamorumt)和指名亚种(M. f. fortis)筑巢行为。结果表明,东方田鼠指名亚种和长江亚种皆能主动获取巢材并建筑质量良好的巢,具有稳定的筑巢行为;东方田鼠两个亚种的筑巢行为在利用巢材能力(P <0.01)和获取巢材能力(P <0.05)上皆具有显著性差异;指名亚种雌雄个体在利用巢材(P <0.05)和获取巢材的能力(P<0.05)上皆具有显著差异,而长江亚种在这两个方面都不存在性别差异。
