Thermal modeling optimization and experimental validation for a single, concentrator solar cell system with a heat sink

A single concentrator solar cell model with a heat sink is established to simulate the thermal performance of the system by varying the number, height, and thickness of fins, the base thickness and thermal resistance of the thermal conductive adhesive. Influence disciplines of those parameters on temperatures of the solar cell and heat sink are obtained. With optimized number, height and thickness of fins, and the thickness values of base of 8, 1.4 cm, 1.5 mm, and 2 mm, the lowest temperatures of the solar cell and heat sink are 41.7℃ and 36.3℃ respectively. A concentrator solar cell prototype with a heat sink fabricated based on the simulation optimized structure is built. Outdoor temperatures of the prototype are tested. Temperatures of the solar cell and heat sink are stabilized with time continuing at about 37℃-38℃ and 35℃-36℃ respectively, slightly lower than the simulation results because of effects of the wind and cloud. Thus the simulation model enables to predict the thermal performance of the system, and the simulation results can be a reference for designing heat sinks in the field of single concentrator solar cells.     

Ruby fluorescence pressure scale： Revisited

Effect of non-hydrostatic stress on X-ray diffraction in a diamond anvil cell (DAC) is studied. The pressure gradient in the sample chamber leads to the broadening of the diffraction peaks, which increase with the hkl index of the crystal. It is found that the difference between the determined d-spacing compressive ratio d/d0 and the real d-spacing compressive ratio dr/d0 is determined by the yield stress of the pressure transmitting media (if used) and the shear modulus of the sample. On the basis of the corrected experiment data of Mao et al. (MXB86), which was used to calibrate the most widely used ruby fluorescence scale, a new relationship of ruby fluorescence pressure scale is corrected, i.e., P = (1904/9.827)[(1+λ/λ0)9.827-1].     

Electrochemical cells with multilayer functional electrodes

Microstructural and chemical changes in a NiO-YSZ electrocatalytic electrode were studied. The microstructural changes in the NiO-YSZ electrocatalytic electrode after the cell operation was compared with the electrode quenched under the applied voltage to suppress the oxidation process. The reversible reduction of NiO into Ni and the formation of intergranular Ni layers at the NiO/YSZ interface were investigated. It was shown that in a compositional range of the NiO-YSZ electrodes from 1/3 to 2/3 the value of the ambipolar conductivity increased with increasing voltage applied to the electrochemical cell. The observed reversible increase in the value of ambipolar conductivity of the electrocatalytic electrode is described in frames of the model of reversible reduction of NiO into Ni under the conditions of cell operation.     

Recognition and elimination of diversified pathogens in insect defense systems

Summary The elimination of infectious non-self by the host defense systems of multicellular organisms requires a variety of recognition and effector molecules. The diversity is generated in somatic cells or encoded in the germ-line. In adaptive immunity in jawed vertebrates, the diversity of immunoglobulins and antigen receptors is generated by gene rearrangements in somatic cells. In innate immunity, various effector molecules and pattern recognition receptors, such as antimicrobial peptides and peptidoglycan recognition proteins, are encoded in the germ-line of multicellular organisms, including insects and jawed vertebrates. In the present review, we discuss how insect host defense systems recognize and eliminate a multitude of microbes via germ-line-encoded molecules, including recent findings that a Drosophila member of the immunoglobulin superfamily is extensively diversified by alternative splicing in somatic immune cells and participates in the elimination of bacteria.     

Electrocatalytic activity of ordered intermetallic PtSb for methanol electro-oxidation

Ordered intermetallic PtSb had been synthesized by arc-melted and then sintering treatment. The electro-oxidation of liquid methanol on PtSb was investigated at room temperature by cyclic voltammetry and chronoamperometry. The results are compared to those at a polycrystalline platinum electrode surface. It was found that PtSb intermetallic was catalytically more active than pure platinum according to the onset potential and current density. X-ray diffraction (XRD) and XPS technologies had been used to investigate the crystal structure and electron effect.     

GaInP2/GaAs/Ge叠层太阳电池材料的低压MOCVD外延生长

本文采用自制的LP-MOCVD设备,外延生长出GaInP₂/GaAs/Ge叠层太阳电池结构片,对电池材料进行了X射线衍射测试分析.另外,采用二次离子质谱仪测试了电池结构的剖面曲线.用此材料做出的叠层太阳电池,AMO条件下光电转换效率η=13.6%,开路电压V_oc=2230mV,短路电流密度J_sc=12.6mA/cm².     

Proton conductivity of phosphoric acid derivative of fullerene

The proton conductive property of methano [60] fullerene diphosphoric acid has been investigated under various humidity conditions at the temperature range between 15 and 45 °C. It shows proton conductivity as high as 10⁻² S cm⁻¹ at 25 °C under relative humidity of 95%. Thermal analyses including TG–DTA and thermal desorption mass spectroscopy (TDS) confirm that the compound is thermally stable up to 200 °C. Proton conduction of the compound depends very much on humidity or water content. The logarithmic conductivity at 25 °C is increased linearly with increasing relative humidity. The activation energy (E_a) estimated from the slope of log(σT) vs. 1/T is decreased from 1.08 to 0.52 eV, as the relative humidity is increased from 40% to 75%. The humidity dependence of conductivity is discussed in the light of the observed hydration isotherm.     

脑细胞激活素药物的化学成分分析

采用日本岛津LC-60A型高压液相色谱仪和美国P-E3030型原子吸收分光光度计，对该药进行了氨基酸、维生素和化学元素的含量测定。结果表明，该药含有18种氨基酸，不少于3种维生素和20几种化学元素，为进一步改进该药物的合理配制方法和临床应用提供了参考数据。     

Long-term depression and other synaptic plasticity in the cerebellum

Cerebellar long-term depression (LTD) is a type of synaptic plasticity and has been considered as a critical cellular mechanism for motor learning. LTD occurs at excitatory synapses between parallel fibers and a Purkinje cell in the cerebellar cortex, and is expressed as reduced responsiveness to transmitter glutamate. Molecular induction mechanism of LTD has been intensively studied using culture and slice preparations, which has revealed critical roles of Ca²⁺, protein kinase C and endocytosis of AMPA-type glutamate receptors. Involvement of a large number of additional molecules has also been demonstrated, and their interactions relevant to LTD mechanisms have been studied. In vivo experiments including those on mutant mice, have reported good correlation of LTD and motor learning. However, motor learning could occur with impaired LTD. A possibility that cerebellar synaptic plasticity other than LTD compensates for the defective LTD has been proposed.     

电沉积处理与染料敏化纳米薄膜太阳电池的优化

采用阳极氧化水解法对染料敏化纳米TiO₂薄膜太阳电池的光阳极进行不同方式的电沉积优化处理.借助x射线衍射仪对处理后的样品进行分析，通过超高分辨率场发射扫描电子显微镜对导电玻璃以及电沉积处理前后纳米多孔薄膜表面进行了粒径和形貌的扫描.染料敏化太阳电池实验测试结果表明，电沉积处理和修饰后可以明显提高光生电子的收集率，增大短路电流密度，提高电池效率. 关键词： 2')" href="#">纳米TiO₂ 染料敏化 电沉积 太阳电池