LTE基站的BBU池规划及传输回传建设分析

分析研究BBU池站点规划关建控制点及LTE基站传输回传解决方案。

Improvement in Performance of Carbon-based Perovskite Solar Cells through Interface Modification with CTAC

Carbon-based perovskite solar cells have attracted much attention,due to their low cost,simple preparation process and high chemical stability.However,the devices exhibit low photoelectric conversion efficiency,owing to the presence of defects and interface impedance between the perovskite active layer and the contact interface.In order to minimize the interfacial defects and improve the charge transfer performance between the perovskite layer and the contact interface,cetyltrimethylammonium chloride(CTAC)was introduced into the lower interface of HTL-free carbon-based perovskite solar cells,because CTAC can be used as interface modification material to passivate the buried interface of perovskite and promote grain growth.It was found that CTAC can not only passivate the interface defects of perovskite,but also improve the crystalline quality of perovskite.As a result,the photovoltaic conversion efficiency of reaches 17.18%,which is 12.5%higher than that of the control group.After 20 days in air with 60%RH humidity,the cell can still maintain more than 90%of the initial efficiency,which provides a new strategy for interfacial passivation of perovskite solar cells.

旋转机械振动监测48通道连续录波及海量数据存储系统的研制

以大型旋转机械多通道连续振动监测为应用背景,借鉴VX I/PX I技术,基于USB-IDE接口卡和FIFO-FIFO数据池缓冲传输方式,研制开放性、模块化、高性价比的旋转机械振动监测48通道连续录波及海量数据存储系统.详细介绍硬件功能模块的设计与开发,在智能仪器、军用ATE等领域具有广泛的适用性和可移植性.

阻击垃圾邮件——赋予Exchange环境更深入的防御能力

垃圾邮件越来越成为企业邮件服务器管理员需要面对的最头疼的问题，本文将告诉你如何在多个环节赋予Exchange环境更深入的防御垃圾邮件的能力，以帮助你真正做到御垃圾邮件于“国门”之外。

Enhanced Photovoltage for Inverted Perovskite Solar Cells Using Delafossite CuCrO_(2) Hole Transport Material

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)has been widely adopted as hole transport material(HTM)in inverted perovskite solar cells(PSCs),due to high optical transparency,good mechanical flexibility,and high thermal stability;however,its acidity and hygroscopicity inevitably hamper the long-term stability of the PSCs and its energy level does not match well with perovskite materials with a relatively low open-circuit voltage.In this work,p-type delafossite CuCrO_(2)nanoparticles synthesized through hydrothermal method was employed as an alternative HTM for triple cation perovskite[(FAPbI_(3))_(0.87)(MAPbBr_(3))_(0.13)]_(0.92)(CsPbI_(3))_(0.08)(possessing better photovoltaic performance and stability than conventional CH3NH3PbI3)based inverted PSCs.The average open-circuit voltage of PSCs increases from 908 mV of the devices with PEDOT:PSS HTM to 1020 m V of the devices with CuCrO_(2)HTM.Ultraviolet photoemission spectroscopy demonstrates the energy band alignment between CuCrO_(2)and perovskite is better than that between PEDOT:PSS and perovskite,the electrochemical impedance spectroscopy indicates CuCrO_(2)-based PSCs exhibit larger recombination resistance and longer charge carrier lifetime than PEDOT:PSS-based PSCs,which contributes to the high VOCof CuCrO_(2)HTM-based PSCs.

A Vehicle Routing Problem Based on Intelligent Batteries Transfer Management for the EV Network

Batteries transfer management is one important aspect in electric vehicle(EV)network's intelligent operation management system.Batteries transfer is a special and much more complex VRP(Vehicle Routing Problem) which takes the multiple constraints such as dynamic multi-depots,time windows,simultaneous pickups and deliveries,distance minimization,etc.into account.We call it VRPEVB(VRP with EV Batteries).This paper,based on the intelligent management model of EV's battery power,puts forward a battery transfer algorithm for the EV network which considers the traffic congestion that changes dynamically and uses improved Ant Colony Optimization.By setting a reasonable tabv range,special update rules of the pheromone and path list memory functions,the algorithm can have a better convergence,and its feasibility is proved by the experiment in an EV's demonstration operation system.

Defect Detection in Raw Si Substrates Using Transmission Polarimetry

Inline characterization for fabrication of silicon wafer PV （photovoltaic） devices may be used to optimize device efficiencies, reduce their performance variance, and their cost of production. In this article, the frozen in strain from a variety of extended defects in silicon is shown to effect the polarization of light transmitted through a silicon substrate due to the photo-elastic effect. Transmission polarimetry on pre-fabricated silicon substrates may be used for identification of extended defects in the materials using a polarization analysis instrument. Instrumentation is proposed for detection of defects in raw silicon wafers for applications like raw silicon wafer sorting, scanning silicon bricks, and inline inspection prior to solar cell metallization. Such analysis may assist with gettering of silicon solar cells, may be implemented in the sorting and rejection procedures in PV device fabrication, and in general shows advantages for detection of defects in silicon wafer solar cell materials and devices.

Electrochemical creation of surface charge transfer channels on photoanodes for efficient solar water splitting

Electrochemical treatment is a popular and efficient method for improving the photoelectrochemical performance of water‐splitting photoelectrodes.In our previous study,the electrochemical activation of Mo‐doped BiVO_(4) electrodes was ascribed to the removal of MoO_(x) segregations,which are considered to be surface recombination centers for photoinduced electrons and holes.However,this proposed mechanism cannot explain why activated Mo‐doped BiVO_(4) electrodes gradually lose their activity when exposed to air.In this study,based on various characterizations,it is suggested that electrochemical treatment not only removes partial MoO_(x) segregations but also initiates the formation of H_(y)MoO_(x) surface defects,which provide charge transfer channels for photogenerated holes.The charge separation of the Mo‐doped BiVO_(4) electrode was significantly enhanced by these charge transfer channels.This study offers a new insight into the electrochemical activation of Mo‐doped BiVO_(4) photoanodes,and the new concept of surface charge transfer channels,a long overlooked factor,will be valuable for the development of other(photo)electrocatalytic systems.

One-pot synthesis of hierarchical CoS/NC@MoS/C hollow nanofibers based on one-dimensional metal coordination polymers for enhanced lithium and sodium-ion storage

Multicomponent metal sulfides have been recognized as promising anode materials for lithium/sodiumion storage given their enticing theoretical capacities. However, the simplification of synthetic processes and the construction of heterogeneous interfaces of multimetal sulfides remain great challenges. Herein,a hierarchical 1T-MoS2/carbon nanosheet decorated Co1–xS/N-doped carbon(Co1–xS/NC@MoS2/C) hollow nanofiber was designed and constructed via a one-pot hydrothermal method using a cobalt-based coordination polymer nanofiber. This nanofiber can transform in-situ into conductive N-doped carbon hollow fibers embedded with active Co1–xS nanoparticles, enabling the epitaxial growth of MoS2 nanosheets.Consequently, the Co1–xS/NC@MoS2/C composites achieve exceptional lithium/sodium-ion storage performance. Compared to MoS2/C microspheres and Co1–xS/NC hollow nanofibers alone, the Co1–xS/NC@MoS2/C hollow nanofibers deliver higher discharge capacities(1085.9 mAh g^-1 for lithium-ion batteries(LIBs) and 748.5 mAh g^-1 for sodium-ion batteries(SIBs) at 100 mA g^-1), better capacity retention(910 mAh g^-1 for LIBs and 636.5 mAh g^-1 for SIBs after 150 cycles at 100 mA g^-1), and increased cycling stability(407.2 mAh g^-1 after 1000 cycles for SIBs at 1000 m A g^-1). Furthermore, the kinetic analysis shows that the lithium/sodium-ion storage processes of the Co1–xS/NC@MoS2/C electrode are mainly controlled by pseudocapacitance behavior. The excellent electrochemical properties can thus be ascribed to the synergy of the MoS2/C nanosheets with the enlarged interlayer spacing, good conductivity of the carbon layers, and the Co1–xS nanoparticles embedded in the hollow nanofibers with extensive reaction sites.

Enhanced photoelectric conversion efficiency of dye-sensitized solar cells by the synergetic effect of NaYF_4:Er^(3+)/Yb^(3+) and g-C_3N_4

TiO2-NaYF4：Er^3＋/Yb^3＋-C3N4 composite photoanodes were successfully designed for the first time. The photoelectric conversion efficiency of TiO2-NaYF4：Er^3＋/Yb^3＋ C3N4 composite cell can result an efficiency of 7.37%, which is higher than those of pure TiO2 cell and TiO2-C3N4 composite cell. The enhancement of the efficiency can be attributed to the synergetic effect of NaYF4：Er^3＋/Yb^3＋ and C3N4. Elec- trochemical impedance spectroscopy analysis revealed that the interfacial resistance of the TiO2-dyelI3^-/I^- electrolyte interface of TiO2-NaYF4：Er^3＋/Yb^3＋-C3N4 composites cell was much smaller than that of pure TiO2 cell. In addition, the TiO2-NaYF4：Er^3＋/Yb^3＋-C3N4 composite cell had longer electron recombination time and shorter electron transport time than that of pure TiO2 cell.

Rational design of SnO_2-based electron transport layer in mesoscopic perovskite solar cells:more kinetically favorable than traditional double-layer architecture

Here,the interfacial synergism of discontinuous spot shaped SnO_2 and TiO_2 mesoporous nanocomposite as electron transfer layer（ETL） underlayer is presented in highly efficient mesoscopic perovskite solar cells（M-PSCs）. Based on this new strategy,strong charge recombination observed in previous SnO_2-based ETLs is suppressed to a great extent as the pathways of charge recombination and energy loss are blocked effectively. Meanwhile,the internal series resistance of entire M-PSC is decreased remarkably. The new ETL is more kinetically favorable to electron transfer and thus results in significant photovoltaic improvement and alleviated hysteresis effect of M-PSCs.

A sintering-free, nanocrystalline tin oxide electron selective layer for organometal perovskite solar cells

Effective electron selective layer （ESL） is critical for the power conversion efficiency in organometal halide- based perovskite solar cells （PSCs）. In this work, a spincoating process has been developed to fabricate high quality nanocrystalline SnO2 film at 100℃ without further sintering at higher temperature. When used as ESL in PSCs, such SnO2 film shows greater electron extraction ability and higher efficiency than TiO2 film processed under similar condition, as evidenced by the efficient time-resolved photoluminescence （TRPL） quenching SnO2/CH3NH3PbI3 film. As a resuit, the SnO2-based PSCs possess higher open circuit voltage of 0.91 V, short circuit current density of 20.73 mA cm^-2, and fill factor of 64.25%, corresponding to a conversion efficiency of 12.10%, compared with 7.16% of TiO2-based PSCs. This demonstrates the great potential of applying spin-coating sintering-free process for the low-cost and large-scale manufacturing of PSCs.

Efficient and stable all-inorganic Sb_(2)(S,Se)_(3)solar cells via manipulating energy levels in MnS hole transporting layers

The use of organic hole transport layer(HTL)Spiro-OMeTAD in various solar cells imposes serious stabil-ity and cost problems,and thus calls for inorganic substitute materials.In this work,a novel inorganic MnS film prepared by thermal evaporation has been demonstrated to serve as a decent HTL in high-performance Sb_(2)(S,Se)_(3)solar cells,providing a cost-effective all-inorganic solution.A low-temperature air-annealing process for the evaporated MnS layer was found to result in a significant positive effect on the power conversion efficiency(PCE)of Sb_(2)(S,Se)_(3)solar cells,due to its better-matched energy band alignment after partial oxidation.Impressively,the device with the optimized MnS HTL has achieved an excellent PCE of about 9.24%,which is the highest efficiency among all-inorganic Sb_(2)(S,Se)_(3)solar cells.Our result has revealed that MnS is a feasible substitute for organic HTL in Sb-based solar cells to achieve high PCE,low cost,and high stability.

Ionic liquid crystal-based electrolyte with enhanced charge transport for dye-sensitized solar cells

A room temperature ionic liquid crystal, 1-dodecyl-3-ethylimidazolium iodide （C12EImI）, and an ionic liquid, 1-decyl-3- ethylimidazolium iodide （Cl0EImI）, have been synthesized, characterized and employed as the electrolyte for dye-sensitized solar cells （DSSC）. The physicochemical properties show that a smectic A （SmA） phase with a lamellar structure is formed in CIzEImI. Both C^2EImI and Cl0EImI have good electrochemical and thermal stability facilitating their use in DSSC. The steady-state voltammograms reveal that the diffusion coefficient of I3- in C^2EImI is larger than that in CmEImI, which is at- tributed to the existence of the SmA phase in Ca2EImI. Because the iodide species are located between the layers of imidazo- lium cations in CjzEImI, exchange reaction-based diffusion is increased with a consequent increase in, the overall diffusion. The electrochemical impedance spectrum reveals that charge recombination at the dyed TiOJelectrolyte interface of a C12EImI-based DSSC is reduced due to the increase in I3- diffusion, resulting in higher open-circuit voltage. Moreover, both short-circuit current density and fill factor of the Cl2EImI based DSSC increase, as a result of the increasing transport of I3 in C^2EImI. Consequently, the photoelectric conversion efficiency of C^2EImI-based DSSC is higher than that of the Cl0EImI-based DSSC.

Electron transport layer driven to improve the open-circuit voltage of CH_3NH_3PbI_3 planar perovskite solar cells

Suitable electron transport layers are essential for high performance planar perovskite heterojunction solar cells. Here, we use ZnO electron transport layer sputtered under oxygen-rich atmosphere at room temperature to decrease the hydroxide and then suppress decomposition of perovskite films. The perovskite films with improved crystallinity and morphology are achieved. Besides, on the ZnO substrate fabricated at oxygen-rich atmosphere, open-circuit voltage of the CH_3NH_3PbI_3-based perovskite solar cells increased by 0.13 V.A high open-circuit voltage of 1.16 V provides a good prospect for the perovskite-based tandem solar cells. The ZnO sputtered at room temperature can be easily fabricated industrially on a large scale, therefore, compatible to flexible and tandem devices. Those properties make the sputtered ZnO films promising as electron transport materials for perovskite solar cells.

Transition metal oxides as hole-transporting materials in organic semiconductor and hybrid perovskite based solar cells

Organic polymer solar cells （OSCs） and organic-inorganic hybrid perovskite solar cells （PSCs） have achieved notable progress over the past several years. A central topic in these fields is exploring electronically efficient, stable and effective hole-transporting layer （HTL） materials. The goal is to enhance hole-collection ability, reduce charge recombination, increase built-in voltage, and hence improve the performance as well as the device stability. Transition metal oxides （TMOs） semiconductors such as NiOx, CuOx, CrOx, MoOx, WO3, and V2O5, have been widely used as HTLs in OSCs. These TMOs are naturally adopted into PSC as HTLs and shows their importance. There are similarities, and also differences in applying TMOs in these two types of main solution processed solar cells. This concise review is on the recent developments of transition metal oxide HTL in OSCs and PSCs. The paper starts from the discussion of the cation valence and electronic structure of the transition metal oxide materials, followed by analyzing the structure-property relationships of these HTLs, which we attempt to give a systematic introduction about the influences of their cation valence, electronic structure, work ftmction and film property on device performance.

Recent progress of interconnecting layer for tandem organic solar cells

This paper has reviewed:(1) the two unique advantages of tandem organic solar cells(OSCs) compared to single OSCs;(2) the challengings as well as strategies to develop qualified interconnecting layer(ICL) for tandem OSCs.More specifically,firstly,the two key advantages unique to tandem OSCs as compared to single OSCs,namely minimizing sub-bandgap transmission and thermalization loss as well as realizing optical thick and electrical thin structures,have been discussed.Secondly,the ICL,as one of the most challenging issue in tandem OSCs that needs to fulfill the optical,electrical and mechanical requirements simultaneously to realize a qualified ICL has been reviewed.As one of the most challenging requirement among the three,the electrical requirement and its corresponding three different solving strategies have been discussed in detail,revealing a bright future for developing a general strategy to realizing qualified ICL composed of different hole transporting layer(HTL) and electron transporting layer(ETL).

Efficient CHzNHzPbl3 perovskite solar cells with 2TPA- n-DP hole-transporting layers

CH3NH3PbI3 perovskite solar cells with 2TPA-n-DP （TPA = 4,4＇-（（1E, I＇E,3E,3＇E）- [1,1＇-biphenyl]4,4＇-diylbis（buta-1,3-diene-4,1-diyl））; DP = bis（N,N-di-p-tolylaniline）; n = 1, 2, 3, 4） as hole-transporting materials （HTMs） have been fabricated. After optimization of the mesoporous TiO2 film thickness, devices based on 2TPA- 2-DP with power conversion efficiencies （PCEs） of up to 12.96% have been achieved, comparable to those of devices with （2,2＇,7,7＇-tetrakis（N,N-di-p- methoxyphenylamine）-9,9＇-spirobifluorene） （spiro-OMeTAD） as HTM under similar conditions. Further time-resolved photoluminescence （PL） measurements showed a fast charge transfer process at the perovskite/2TPA-2-DP interface. With the aid of electrochemical impedance spectra, a study of the electron blocking ability of 2TPA-2-DP in the device reveals that the presence of 2TPA-2-DP can greatly increase charge transfer resistance at the HTM/Au interface in the device, thus reducing the recombination. Furthermore, the perovskite solar cells based on these four HTMs exhibit ~ood stability after testin~ for one month.

Band alignment towards high-efficiency NiOx-based Sn-Pb mixed perovskite solar cells

Narrow-bandgap tin-lead(Sn-Pb)mixed perovskite solar cells(PSCs)play a key role in constructing perovskite tandem solar cells that are potential to overpass Shockley-Queisser limit.A robust,chemically stable and lowtemperature-processed hole transporting layer(HTL)is essential for building high-efficiency Sn-Pb solar cells and perovskite tandem solar cells.Here,we explore a roomtemperature-processed NiOx(L-NiOx)HTL based on nanocrystals(NCs)for Sn-Pb PSCs.In comparison with hightemperature-annealed NiOx(H-NiOx)film,the L-NiOx film shows deeper valence band and lower trap density,which increases the built-in potential and reduces carrier recombination,leading to a power conversion efficiency of 18.77%,the record for NiOx-based narrow-bandgap PSCs.Furthermore,the device maintains about 96%of its original efficiency after 50 days.This work provides a robust and room-temperatureprocessed HTL for highly efficient and stable narrow-bandgap PSCs.

Self-doped n-type small molecular electron transport materials for high-performance organic solar cells

Two naphthalene diimide （NDI） and perylene diimide （PDI） based n-type water/alcohol soluble small molecules （NFN and PFP） are designed and utilized as electron transport layers （ETLs） for organic solar cells （OSCs）. NFN and PFP are synthesized by using Sonogashira coupling from alkynyl modified fluorene with mono-bromo substituted NDI and PDI. Density functional theory study results of NFN and PFP show that they possess excellent planarity due to the employment of triple bonds as connection units. Moreover, it was shown by electron paramagnetic resonance study that both NFN and PFP possess obvious self-doping behaviors, which may effectively enhance their charge transporting capability as ETLs in OSCs. Power conversion efficiencies of 8.59% and 9.80% can be achieved for OSCs with NFN and PFP as ETLs, respectively. The higher power conversion efficiency （PCE） of PFP based photovoltaic device is originated from the stronger doping property and higher mobility of PFR