论小型三相交流同步发电机的重量密度

研究数10年来电机发展的历史及各种发电机系列产品统计数字,提出可用一个新概念──“重量密度”来衡量电机的水平。阐述了中小型同步发电机所用绝缘等级每升高一级,电机单位功率所占重量(质量)平均减轻20.53％。从而证实在调整产品结构中,应首先采用F级绝缘新材料来代替B级绝缘材料,以降低重量密度,提高经济效益。

相对密度-重量法在线监控软袋输液的装量

目的:建立在线监控软袋输液装量的方法。方法:采用相对密度法将药液的装量体积折算为药液的重量,确定药液最小装量和标示装量的判定标准,在灌装前、中、后各时段,采用称重法在线监控药液的装量。结果:采用称重法在线监控药液的重量能准确反映软袋输液的体积装量。结论:该方法操作简便,又节约成本,可作为在线检查软袋输液装量的标准。

相对密度-重量法准确测定小容量注射剂的装量

目的:探讨一种简便、准确、结果判定无争议的小容量注射剂装量检查新方法。方法:以20℃时纯化水相对密度1.000为基数分别测定待检批次注射剂的相对密度,再分别精确称定该批次每支药液的重量,折算成准确的体积数,并提出了小容量注射剂装量判定新的标准。结果:新方法无需标定玻璃量器具,去除了量筒刻度上人为估读误差,操作简便。结论:相对密度-重量法测定小容量注射剂装量快速、准确,真实反映了每支安瓿内的药液装量。

固态储氢技术现状与发展趋势分析

氢能被认为是能源转型、工业及交通领域深度脱碳的关键路径。综述了固态储氢技术现状和发展趋势,梳理了物理吸附、化学储氢和金属氢化物等固态储氢技术路线以及美国能源部等机构提出的重量储氢密度、体积储氢密度、循环寿命和系统成本等关键技术参数的发展目标,指出目前存在的技术经济问题和改进方向,分析了固态储氢应用场景和潜力,并提出未来技术发展、系统集成优化及应用方向等建议,为开展固态储氢技术研究及工程示范提供思路和参考。

圆果化香芽种群结构初步研究

以圆果化香(Platycaryalongipes)植株的芽为基本构件单元,对贵州中部喀斯特山地不同坡位上8-12年生植株的芽种群结构进行研究,结果表明:圆果化香芽种群芽总量分配随枝级发生变化,芽数量最多的枝级为树冠中间部位的二级或三级枝,树冠表层的末生枝和紧靠树干的一级枝芽数量较少。各枝级上的新生枝的芽数量高于多次生枝。对圆果化香树冠空间拓展意义最大、芽萌展成枝的潜势最高的顶芽分布于末生枝的新生枝上,其芽密度和芽重量密度最高。从山顶至下部,植株芽种群数量、新生枝的芽量减少,但山中部新生芽量和活芽量最多,顶芽重量密度和侧芽重量密度最低,山上部最少,顶芽重量密度和侧芽重量密度大。

怎样选购纯毛地毯

一看原料:优质纯毛地毯的原料一般是精细羊毛手工编织而成,其毛长而均匀,手感柔软、舒适、富有弹性、无硬根;劣质地毯的原料往往混有发霉变质的劣质毛以及腈纶、丙纶纤维等,其毛短且根粗细不均,手摸时无弹性,有硬根。 二看外观优质纯毛地毯图案清晰美观,绒面富有光泽,色彩鲜艳均匀,花纹层次分明,正面毛绒密结柔软,倒顺一致;

Full tensor gravity gradiometry data inversion:Performance analysis of parallel computing algorithms

We apply reweighted inversion focusing to full tensor gravity gradiometry data using message-passing interface （MPI） and compute unified device architecture （CUDA） parallel computing algorithms, and then combine MPI with CUDA to formulate a hybrid algorithm. Parallel computing performance metrics are introduced to analyze and compare the performance of the algorithms. We summarize the rules for the performance evaluation of parallel algorithms. We use model and real data from the Vinton salt dome to test the algorithms. We find good match between model efficiency and feasibility of parallel computing gravity gradiometry data. and real density data, and verify the high algorithms in the inversion of full tensor

Corrosion behaviors and mechanism of electroless Ni-Cu-P/n-TiN composite coating

In the present investigation, electroless Ni-Cu-P/n-TiN composite coating was prepared using alkaline citrate-based bath. X-ray diffraction （XRD）, scanning electron microscopy（SEM）, energy-dispersive spectroscopy（EDS）, electrochemical measurements, weight loss tests and Raman spectrometer were used to character the properties of the coating. As the Cu content increased from 7.3 wt% to 24.8 wt%, the corrosion current density of the Ni-Cu-P/n-TiN coating decreased from 10.80 to 4.34 ~tA. And the inclusion of Cu in NiP alloy resulted in refinement and less porosity in microstructure. The addition of TiN resulted in a slight decline in anti-corrosion property of the coating. As the mass loss test showed, Ni-24.8%Cu-P exhibited perfect corrosion resistance. Studies by Raman spectroscopy on coatings proved that Cu（II）3（PO4）（OH）3, Cu（OH）2 and CuO were examined while no compound of nickel was found, and Cu exhibited preferred corrosion in saline solution, providing cathodic protection to Ni alloy.

Theoretical Investigation on Triplet Excitation Energy Transfer in Fluorene Dimer

Triplet-triplet energy transfer in fluorene dimer with electronic structure calculations. The two is investigated by combining rate theories key parameters for the control of energy transfer, electronic coupling and reorganization energy, are calculated based on the diabatic states constructed by the constrained density functional theory. The fluctuation of the electronic coupling is further revealed by molecular dynamics simulation. Succeedingly, the diagonal and off-diagonal fluctuations of the Hamiltonian are mapped from the correlation functions of those parameters, and the rate is then estimated both from the perturbation theory and wavepacket diffusion method. The results manifest that both the static and dynamic fluctuations enhance the rate significantly, but the rate from the dynamic fluctuation is smaller than that from the static fluctuation.

Estimation on Local Energy Density in Relativistic Heavy Ion Collisions

Energy density for the central region in relativistic heavy ion collisions can be estimated via the pseudorapidity distribution of transverse energy. The way to estimate the local energy density for the central region in relativistic heavy ion collisions is proposed, in which only final state particles emitted from the same source are included. The arrived energy density in NA49 experiments is about 1.03 GeV/fm3.

Quantum Phase Transitions and Dimerized Phases in Frustrated Spin Ladder

In this paper, we study the phase diagram of a frustrated spin ladder model by applying the bosonization technique and the density-matrix renormalization-group （DMRG） algorithm. Effect of the intra-ehain next-nearest- neighbor （NNN） super-exchange interaction is investigated in detail and the order parameters are calculated to detect the emergence of the dimerized phases. We find that the intra-chain NNN interaction plays a key role in inducing dimerized phases.

金属储氢材料的性能边界条件分析

规模化储运氢是未来氢产业化的发展趋势。国内目前常采用高压氢气作为储运的形式，其最高操作为20MPa。更高压力的气氢、液氢等方式未在国内取得民用资格。同时其他的有可能的储运氢方式，如金属氢化物、化学液态载体都被广泛的研究和讨论。因此探讨何种材料适用于规模化储运氢是必要的。在能耗分析的基础上，建立一种确定规模化储运氢材料性能边界条件的方法。以20MPa高压氢的储运能耗为标准，计算了不同释氢反应生成焓值时，材料储氢比的边界值。结果表明，储氢材料释氯压力达到0．5MPa以上，且当运输距离越长时，金属储氢材料有更高的优势，当距离大于800km时，除合金外大多数单质和复合金属氢化物都可以满足要求。当以正在试验中25，35MPa的气氢为参考，从能耗的角度，运输距离达到1500km以上，金属储氢材料才有明显的优势。未来在规模化储运氢材料的选择上，应考虑接近能耗要求的材料。

Hierarchical flower-like spinel manganese-based oxide nanosheets for high-performance lithium ion battery

Hierarchical flower-structured two-dimensional(2 D)nanosheet is favorable for electrochemical reactions.The unique structure not only exposes the maximized active sites and shortens ion/electron diffusion channels,but also inhibits the structural strain during cycling processes.Herein,we report the hierarchical flower-like pure spinel manganese-based oxide nanosheets synthesized via a template-orientated strategy.The oriented template is fabricated by decomposition of carbonate obtained from"bubble reaction",via an alcoholassisted hydrothermal process.The resultant spinel manganese-based oxide nanosheets simultaneously possess excellent rate capability and cycling stability.The high-voltage LiNi0.5Mn1.5O4(LNMO-HF)has a uniform phase distribution without the common impurity phase LixNi1-xO2 and NixO.Besides,the LNMO-HF delivers high discharge capacity of142.6 mA h g-with specific energy density of 660.7 W h kg 1 at 1 C under 55℃.More importantly,the template-orientated strategy can be extended to the synthesis of LiMn2 O4(LMO),which can achieve 88.12%capacity retention after 1000 cycles.

Analysis of Generalized Ghost Dark Energy in LQC and Galileon Gravity

A so-called ghost dark energy was recently proposed to explain the present acceleration of the universe.The energy density of ghost dark energy,which originates from Veneziano ghost of Quantum Chromodynamics(QCD),in a time dependent background,can be written in the form,ρD=αH + βH^2 where H is the Hubble parameter.We investigate the generalized ghost dark energy(GGDE) model in the setup of loop quantum Cosmology(LQC) and Galileon Cosmology.We study the cosmological implications of the models.We also obtain the equation of state and the deceleration parameters and differential equations governing the evolution of this dark energy model for LQC and Galileon Cosmology.

Influence of the symmetry energy on the balance energy of the directed flow

The influence of the density-dependent symmetry energy on the balance energy （Ebal） of directed flow from heavy ion collisions （HICs） at incident energies covered by INDRA and MSU experiments is studied, using the updated version of the ultra- relativistic quantum molecular dynamics （UrQMD） model, especially adapted to low-energy heavy ion collisions （HICs）. Four mass-symmetric reactions with total mass numbers between 192 and 394 are chosen for investigating the influence of the symmetry energy on the system-mass dependence of Eual. The results show that the uncertainty in the density dependence of the symmetry potential causes changes of Ebal of the order of several MeV, depending on the type of particle considered. The Ebal of neutrons from HICs is particularly sensitive to the density dependence of the symmetry potential energy, while the system-mass dependence of EbaI of Z = 1 particles is not.