110 kV双断口快速开关效率优化分析

电磁斥力效率的优化研究,以往研究主要针对斥力盘、线圈等关键零件的结构优化和参数匹配,以及预充电电容的电压和容值的优化分析,很少有关于开关辅助支撑结构件对效率影响的分析研究。不同结构形式和材质的辅助支撑结构件对斥力盘效率有着不可忽视的影响。文中以快速开关支撑板作为分析研究对象,在不改变样机结构形式的前提下,提出了通过设计导磁板,对支撑板开槽等方式,降低支撑板的涡流损耗,提高电磁斥力效率。文章最后,基于仿真结果,对一款110 kV双断口快速开关样机进行了改造设计。试验结果表明,在容值不变情况下,增加导磁板或者支撑板开槽可以有效降低电容预充电压,提高斥力机构效率。

基于热电能的传感器在路面中的智能应用

投入使用多年的基础设施需要预防性养护措施保证其正常的使用功能,利用更多的创新型传感器确保基础设施的使用寿命,将是今后一个明智且值得采纳的方式。在考虑降低基础设施费用和确保嵌入式传感器的长期使用性能方面,如何保证传感器的能量供给是必须考虑的重要环节。该文论述了采用热电提供能量的传感器的初步研究成果,体现了能够长期监测路面性能的一种创新性策略。

Mechanical model for failure modes of rock and soil under compression

The failure modes of rock and soil under compression are complex phenomena that have not been explained in a mechanical perspective. However, large amounts of studies indicate that the failure modes of rock and soil samples can be categorized into eight types. In this work, the inner tensile stress and the dissipation and conversion of energy of rock and soil under compression are analyzed, then the effective conversion coefficient of energy is deduced, thus the tensile failure criterion of rock and soil under compression is established. Combined with the shear strength criterion of Mohr–Coulomb, a tensile joint shear strength criterion for rock and soil under compression is built. Therefore, a mechanical criterion model concerning the failure modes of rock and soil under compression is established and verified by tests. This model easily explains the test results in the existing literature and many natural phenomena, such as collapse.

Photoinhibition and Photooxidation in Leaves of indica and japonica Rice Under Different Temperatures and Light Intensities

Physiological indices related to the efficiency (F-v/F-m) of light energy conversion in PS II and the peroxidation of membrane lipid were measured in leaves of Oryza sativa L. sp. indica rice cv. 'Shanyou 63' and sp. japonica rice cv. '9516'' under different temperatures and fight intensities for 4 days. No changes in F-v/F-m and membrane lipid peroxidation product (MDA) were observed, so neither photoinhibition nor photooxidation happened in both rice cultivars under moderate temperature and medium light intensity. However, F-v/F-m dropped obviously with no change in MDA contents, and photoinhibition appeared in indica rice cv. 'Shanyou 63' under medium temperature and strong light intensity. Furthermore, both photoinhibition and photooxidation were observed in two rice cultivars under chilling temperature and strong light intensity. Experiments with inhibitors under chilling temperature and strong light intensity showed that indica rice had a decrease in DI protein content and SOD activity, and the extent of inhibition of xanthophyll. cycle and nonphotochemical quenching (qN) was larger, and a higher level of MDA was observed. The photoinhibition and photooxidation in indica rice were more distinct as compared with japonica rice. The authors suggested that PS II light energy conversion efficiency (F-v/F-m) and membrane lipid peroxidation were the key indices for the detection of photooxidation.

Influence of Chemical Effect on the Kβ/Kα Intensity Ratios and Kβ Energy Shift of Co, Ni, Cu, and Zn Complexes

Chemical effects on the Kβ/Kα intensity ratios and △E energy differences for Co, Ni, Cu, and Zn complexes were investigated. The samples were excited by 59.5 keV γ-rays from a ^241Am annular radioactive source. K X-rays emitted by samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. We observed the effects of different ligands on the Kβ/Kα intensity ratios and △E energy differences for Co, Ni, Cu, and Zn complexes. We tried to investigate chemical effects on central atoms using the behaviors of different ligands in these complexes. The experimental values of Kβ/Kα were compared with the theoretical and other experimental values of pure Co, Ni, Cu, and Zn.

Study of Back Contacts for CdTe Solar Cells

ZnTe/ZnTe∶Cu layer is used as a complex back contact. The parameters of CdTe solar cells with and without the complex back contacts are compared. The effects of un-doped layer thickness, doped concentration and post-deposition annealing temperature of the complex layer on solar cells performance are investigated.The results show that ZnTe/ZnTe∶Cu layer can improve back contacts and largely increase the conversion efficiency of CdTe solar cells. Un-doped layer and post-deposition annealing of high temperature can increase open voltage. Using the complex back contact, a small CdTe cell with fill factor of 73.14% and conversion efficiency of 12.93% is obtained.

Muscle Aerobic Capacity and Filleting Yield of Farmed Fish Species in the Mediterranean Sea

In the present work, we compared indices of metabolism and feed conversion efficiency of a semi benthic and two pelagic mari-cultured fish species in the Mediterranean Sea. The metabolism of fish species varies according to habitat and ecophysiological adaptations. For example, with increasing depth, some species may exhibit adaptations to lower temperature and hypoxic conditions with a reduction in mass specific metabolic rate. Meagre （Argyrosomus regius） is a semi-benthic fish found at depths between 30 m and 300 m. Sea bass （Dicentrarhus labrax） and gilthead sea bream （Sparus auratus） are semi-pelagic fish species widely cultivated in the Mediteranean Sea. The aerobic metabolic potential and feed conversion efficiency of meagre were very different from the sea bass and gilthead sea bream. Compared to these two semic-pelagic fish species, meagre exhibited less efficient feed conversion rate, fillet yield. The results provide an estimate of the quantity of fish required to produce 1 kg of fillet weight, an estimation which is required for the operational management of fish processing companies and for estimating the wastes of fish processing factories during filleting.

中欧季节制冷能效系数SEER的转换算法研究

为实现中欧空调制冷能效系数SEER之间的转化计算,本文以中欧能效标准规定的SEER定义式为基准计算式,提出利用标准计算中关于工况转化的分段插值方法,建立中欧测试参数的转换关系式,以此构建能效间的转化算法,实现了通过测试国标规定的5组工况,同时计算获得中欧SEER,经实验验证,该算法精度高达99.66%。

15.3% efficiency all-small-molecule organic solar cells enabled by symmetric phenyl substitution

Synergistic optimization of donor-acceptor blend morphologyis a hurdle in the path of realizing efficient non-fullerene small-molecule organic solar cells(NFSMOSCs)due to the anisotropic conjugated backbones of both donor and acceptor.Therefore,developing a facile molecular design strategy to effectively regulate the crystalline properties of photoactive materials,and thus,enable the optimization of blend morphology is of vital importance.In this study,a new donor molecule B1,comprising phenyl-substituted benzodithiophene(BDT)central unit,exhibits strong interaction with the non-fullerene acceptor BO-4 Cl in comparison with its corresponding thiophene-substituted BDT-based material,BTR.As a result,the B1 is affected and induced from an edgeon to a face-on orientation by the acceptor,while the BTR and the acceptor behave individually for the similar molecular orientation in pristine and blend films according to grazing incidence wide angle X-ray scattering results.It means the donor-acceptor blend morphology is synergistically optimized in the B1 system,and the B1:BO-4 Cl-based devices achieve an outstanding power conversion efficiency(PCE)of 15.3%,further certified to be 15.1%by the National Institute of Metrology,China.Our results demonstrate a simple and effective strategy to improve the crystalline properties of the donor molecule as well as synergistically optimize the morphology of the all-small-molecule system,leading to the high-performance NFSM-OSCs.

Boosting solar steam generation by structure enhanced energy management

Interfacial solar-steam generation is a promising and cost-effective technology for both desalination and wastewater treatment.This process uses a photothermal evaporator to absorb sunlight and convert it into heat for water evaporation.However solar-steam generation can be somewhat inefficient due to energy losses via conduction,convection and radiation.Thus,efficient energy management is crucial for optimizing the performance of solar-steam generation.Here,via elaborate design of the configuration of photothermal materials,as well as warm and cold evaporation surfaces,performance in solar evaporation was significantly enhanced.This was achieved via a simultaneous reduction in energy loss with a net increase in energy gain from the environment,and recycling of the latent heat released from vapor condensation,diffusive reflectance,thermal radiation and convection from the evaporation surface.Overall,by using the new strategy,an evaporation rate of 2.94 kg m^-2 h^-1,with a corresponding energy efficiency of solar-steam generation beyond theoretical limit was achieved.

An integrated thermoelectric-assisted photoelectrochemical system to boost water splitting

Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement of 1.23 eV and kinetic energy loss of about 0.6 eV, a photo-voltage of 1.8 V produced by PEC cells is generally required for spontaneous water splitting. Therefore, the minimum bandgap of1.8 eV is demanded for photoactive materials in single-photoelectrode PEC cells, and the bandgap of about 1 eV for back photoactive materials is appropriate in tandem PEC cells. All these PEC cells cannot effectively utilize the infrared light from 1250 to 2500 nm. In order to realize the full spectrum utilization of solar light, here, we develop a solar-driven PEC water splitting system integrated with a thermoelectric device. The key feature of this system is that the thermoelectric device produces a voltage as an additional bias for the PEC system by using the temperature difference between the incident infrared-light heated aqueous electrolyte in the PEC cell as the hot source and unirradiated external water as the cold source. Compared to a reference PEC system without the thermoelectric device, this system has a significantly improved overall water splitting activity of 1.6 times and may provide a strategy for accelerating the application of full spectrum solar light-driven PEC cells for hydrogen production.

Recent advances in non-noble electrocatalysts for oxidative valorization of biomass derivatives

Electrocatalysis is deemed as a promising approach for sustainable energy conversion and chemical production.Although a variety of cathode reactions(e.g.,hydrogen evolution and CO_(2)/N_(2)reduction)produce valuable fuels and chemicals,the extensively studied oxygen evolution reaction(OER)at anode only generates O_(2),which is not a high-value product.Substituting the OER with thermodynamically more favorable biomass derivative oxidation reactions(BDORs)not only enables energy-saving electrocatalysis,but also provides value-added anode products.Recent achievements have demonstrated that non-noble electrocatalysts are promising for BDORs.Herein,we provide a comprehensive review on recent achievements in the field of electrochemical BDORs catalyzed by non-noble catalysts.We start by summarizing the electrocatalytic oxidation of different types of biomass-derived substrates,aiming to show the advantages of the electrocatalytic pathway and to introduce the state-of-the-art non-noble catalysts.The reaction mechanisms of non-noble-material-catalyzed BDORs are then summarized and classified into three types according to the acceptor of hydrogen species during the dehydrogenation of biomass derivatives.Subsequently,discussions are devoted to the strategies for promoting the performances of non-noble electrocatalysts.Finally,we propose our opinions regarding future trends and major challenges in this field.

Optimizing the component ratio of PEDOT:PSS by water rinse for high efficiency organic solar cells over 16.7%

For the state-of-the-art organic solar cells(OSCs),PEDOT:PSS is the most popularly used hole transport material for the conventional structure.However,it still suffers from several disadvantages,such as low conductivity and harm to ITO due to the acidic PSS.Herein,a simple method is introduced to enhance the conductivity and remove the additional PSS by water rinsing the PEDOT:PSS films.The photovoltaic devices based on the water rinsed PEDOT:PSS present a dramatic improvement in efficiency from 15.98%to 16.75%in comparison to that of the untreated counterparts.Systematic characterization and analysis reveal that although part of the PEDOT:PSS is washed away,it still leaves a smoother film and the ratio of PEDOT to PSS is higher than before in the remaining films.It can greatly improve the conductivity and reduce the damage to substrates.This study demonstrates that finely modifying the charge transport materials to improve conductivity and reduce defeats has great potential for boosting the efficiency of OSCs.

Synergistic high efficiency and low energy loss of all-small-molecule organic solar cells based on benzotriazole-basedπ-bridge unit

Reducing energy loss(V_(loss))is one of the most crucial challenges in organic photovoltaic cells.The V_(loss),determined by the differences between the optical band gap(E_(g))of the active layer material and the open-circuit voltage(V_(oc))of the device,is generally alleviated by lowering the energy difference between the lowest unoccupied molecular orbital(LUMO)and highest occupied molecular orbital(HOMO)level of the donor(D)and acceptor(A).In this work,we synthesized two A-π-D-π-A-type small-molecule donors(SMDs)SM-benzotriazole(BTz)-1 and SM-BTz-2 by introducing a BTzπ-bridge unit and terminal regulation.The BTzπ-bridge unit significantly lowers the HOMO energy level of SMDs,resulting in high V_(oc)and high mobility,achieving a balance of low energy loss(<0.5 eV)and high efficiency.Ultimately,the organic solar cells based on SM-BTz-2 as the donor and Y6 as the acceptor obtain a high V_(oc)of 0.91 V,J_(sc) of 22.8 mA cm^(−2),fill factor of 68%,and power conversion efficiency(PCE)of 14.12%,which is one of the highest efficiencies based on the SMDs with triazoleπ-bridges to date.What’s more,the BTzπ-bridge unit is a potential unit that can improve mobility and reduce energy loss.

n-Octyl substituted quinoxaline-based polymer donor enabling all-polymer solar cell with efficiency over 17%

Recently, the power conversion efficiencies(PCEs) of all-polymer solar cells(all-PSCs) have increased rapidly. To further increase the PCE of all-PSCs, it is necessary to create new donor polymers matching the polymer acceptors. In this paper, we synthesize a new quinoxaline-based polymer donor PBQ8 with n-octyl side chain on the quinoxaline unit, which possesses the same skeleton structure to the previously reported PBQ5(with isooctyl side chain). The effects of alkyl side chains on the physicochemical properties of the polymer donor were investigated. In comparison with PBQ5, PBQ8 exhibits stronger intermolecular interactions and better molecular packing. When blending with polymer acceptor PY-IT, the PBQ8:PY-IT based devices demonstrated a higher PCE value of 17.04%, which is one of the highest PCEs occurred in the all-PSCs. And the PBQ5:PY-IT(PCE 15.56%, Voc0.907 V, FF 69.72%, and Jsc24.60 m A cm^(-2)) is much lower. The PBQ8:PY-IT blend displayed more efficient exciton dissociation, better molecular stacking properties, preferable phase separation and higher mobility. These indicate that as an effective method, side chain engineering can improve the efficiency of the all-PSCs.

Three dimensional carbon substrate materials for electrolysis of water

Water splitting is an important approach for energy conversion to obtain hydrogen and oxygen. Apart from solar water splitting, electrochemical method plays a key role in the booming field, and it is urgent to develop novel and efficient catalysts to accelerate water splitting reaction. Recently, newly emerging self-supported materials, especially three dimensional（3D） carbon substrate electrochemical catalysts, have attracted great attention benefiting from their fantastic catalytic performances, such as large surface area,enhanced conductivity, tunable porosity, and so on. This review summarizes the outstanding materials used for hydrogen evolution reaction and oxygen evolution reaction. And catalysts that acted as both anode and cathode in two-electrode systems for overall water splitting are introduced systematically. The opportunities and challenges of 3D carbon substrate materials for electrochemical water splitting are proposed.

High-efficiency colorful perovskite solar cells using TiO2 nanobowl arrays as a structured electron transport layer

The rapid development of perovskite solar cells(PSCs) has stimulated great interest in the fabrication of colorful PSCs to meet the needs of aesthetic purposes in varied applications including building integrated photovoltaics and wearable electronics. However, it remains challenging to prepare high-efficiency PSCs with attractive colors using perovskites with broad optical absorption and large absorption coefficients. Here we show that high-efficiency PSCs exhibiting distinct structural colors can be readily fabricated by employing Ti O2 nanobowl(NB) arrays as a nanostructured electron transport layer to integrate with a thin overlayer of perovskite on the NB arrays. A new crystalline precursor film based on lead acetate was prepared through a Lewis acid-base adduct approach, which allowed for the formation of a uniform overlayer of high-quality CH3 NH3 Pb I3 crystals on the inner walls of the NBs. The PSCs fabricated using the Ti O2 NB arrays showed angle-dependent vivid colors under light illumination. The resultant colorful PSCs exhibited a remarkable photovoltaic performance with a champion efficiency up to16.94% and an average efficiency of 15.47%, which are recordbreaking among the reported colorful PSCs.

Intermediate phase-enhanced Ostwald ripening for the elimination of phase segregation in efficient inorganic CsPbIBr_(2)perovskite solar cells

Mixed halide perovskites with the ability to tune bandgaps exhibit attractive applications in tandem solar cells,building integrated photovoltaic and wavelength-tunable light-emitting devices.However,halide demixing under illumination or in the dark with a charge-carrier injection in both hybrid and inorganic perovskites results in bandgap instability and current-density-voltage(J-V)hysteresis,which can significantly hamper their application.Here,we demonstrate that halide segregation and J-V hysteresis in mixed halide inorganic CsPbIBr_(2)solar cells can be effectively mitigated by introducing an intermediate phase-enhanced Ostwald ripening through the control of the chemical composition in the CsPbIBr_(2)precursor solution.Excess amounts of either PbBr_(2)or CsI are incorporated into originally even molar amounts of PbBr_(2)and CsI precursor solutions.With the PbBr_(2)-excess,we observed an enlarged perovskite grain size,no detectable halide phase segregation at the grain boundaries nor the perovskite/TiO2 interface,an increased minority carrier lifetime,a reduced J-V hysteresis,and an improved solar-cell performance.However,different CsI:PbBr_(2)stoichiometric ratios were found to have different effects on the performance of the perovskite solar cell.The excessive lead phase is reactive with the dimethyl sulfoxide(DMSO)in the precursor solution to form the Pb(I,Br)2·DMSO complex and the quasi-twodimensional(2D)CsPb_(2)(I,Br)5,which are conducive to Ostwald maturation and defect extinction.Finally,the CsPbIBr_(2)solar cell with a PbBr_(2)-excess precursor composition reaches a power conversion efficiency(PCE)of 9.37%(stabilized PCE of 8.48%)and a maximum external quantum efficiency of over 90%.

Intrinsically inert hyperbranched interlayer for enhanced stability of organic solar cells

Device stability becomes one of the most crucial issues for the commercialization of organic solar cells(OSCs) after high power conversion efficiencies have been achieved. Besides the intrinsic stability of photoactive materials, the chemical/catalytic reaction between interfacial materials and photoactive materials is another critical factor that determines the stability of OSC devices. Herein, we design and synthesize a reaction-inert rylene diimide-embedded hyperbranched polymer named as PDIEIE, which effectively reduces the work function of indium tin oxide electrode from 4.62 to 3.65 eV. Meanwhile, PDIEIE shows negligible chemical reaction with high-performance photoactive materials and no catalytic effect under strong ultraviolet illumination, resulting in much better photo-stability of OSCs with PDIEIE cathode interlayer(CIL), relative to the traditional CILs, including most-widely used metal oxides and polyethyleneimine derivatives.

A novel dopant for spiro-OMeTAD towards efficient and stable perovskite solar cells

2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency perovskite solar cells(PSCs). In general, it is prepared by a halogen solvent(chlorobenzene, CBZ) and needs an ion dopant(lithium bis(trifluoromethanesulfonyl)imide, Li-TFSI) to improve its conductivity and hole mobility. However, such a halogen solvent is not environmentally friendly and the widely used LiTFSI dopant would affect the stability of PSCs. Herein, we develop a non-halogen solvent-tetrahydrofuran(THF)-prepared spiro-OMeTAD solution with a new p-type dopant,potassium bis(fluorosulfonyl)imide(K-FSI), to apply into PSCs. By this strategy, high-hole-mobility spiro-OMeTAD film is achieved. Meanwhile, the potassium ions introduced by diffusion into perovskite surface passivate the interfacial defects. Therefore, a hysteresis-free champion PSC with an efficiency of 21.02% is obtained, along with significantly improved stability against illumination and ambient conditions. This work provides a new strategy for HTMs toward hysteresis-free high-efficiency and stable PSCs by substituting dopants.