Tailoring Mg^(2+)Solvation Structure in a Facile All-Inorganic[Mg_(x)Li_(y)Cl2_(x+y)·nTHF]Complex Electrolyte for High Rate and Long Cycle-Life Mg Battery

A high-performance all-inorganic magnesium-lithium chloride complex(MLCC)electrolyte is synthesized by a simple room-temperature reaction of LiCl with MgCl_(2) in tetrahydrofuran(THF)solvent.Molecular dynamics simulation,density functional theory calculation,Raman spectroscopy,and nuclear magnetic resonance spectroscopy reveal that the formation of[Mg_(x)Li_(y)Cl_(2x+y)·nTHF]complex solvation structure significantly lowers the coordination number of THF in the first solvation sheath of Mg^(2+),which significantly enhances its de-solvation kinetics.The MLCC electrolyte presents a stable electrochemical window up to 3.1 V(vs Mg/Mg^(2+))and enables reversible cycling of Mg metal deposition/stripping with an outstanding Coulombic efficiency up to 99%at current densities as high as 10 mA cm^(-2).Utilizing the MLCC electrolyte,a Mg/Mo_(6)S_(8) full cell can be cycled for over 10000 cycles with a superior capacity retention of 85 mA h g^(-1) under an ultrahigh rate of 50 C(1 C=128.8 mA g^(-1)).The facile synthesis of highperformance MLCC electrolyte provides a promising solution for future practical magnesium batteries.

Morphology and formation mechanism of sand shadow dunes on the Qinghai-Tibet Plateau

The formation and development of dunes depend on wind-blown sand movement which is affected by the characteristics of sand material, topography, wind regimes and other factors. In this paper, we investigated two sand shadow dune groups in Shigatse and Za＇gya Zangbo of Tibet and an individual dune in Da Qaidam of Qinghai, and analyzed their topographies and morphologies, and the physical characteristics of the sand, wind regime and sand transport. Formed under harsh conditions behind hills, these mature sand shadow dunes are hundreds of meters long, have significant ridges and crescent dunes downwind, and have a hill pass on one or both sides. Wind tunnel experiments revealed that the hill gap and wind velocity are important factors in the formation of these dunes Sand shadow dunes formed only when the gap spacing is two-thirds of the hill height. When wind velocities are 20 m/s, the sand body is divided into two parts. The hill pass allows the transport of sand by wind, creating a ＂nar- row-pipe effect＂, which causes the transported material to gradually accumulate in the center of the shadow zone. We observed that the following are needed for sand shadow dunes to form： （1） strong winds, sufficient sand, suitable obstacles and a dry climate; （2） one or both sides of the obstacle forming the shadow zone must have a hill pass; and （3） the windward side of the obstacle must have a wide, flat area, providing adequate spacing for wind flow and transport of material and the leeward side must have a sufficiently broad, flat area to allow the release of the transported material. Research results on these newly discovered dunes on the Qinghai-Tibet Plateau could contribute to the understanding of dune geomorphology.

FPSO Global Strength and Hull Optimization

Global strength is a significant item for floating production storage and offloading(FPSO) design, and steel weight plays an important role in the building costs of FPSO. It is the main task to consider and combine these two aspects by optimizing hull dimensions. There are many optional methods for the global strength analysis. A common method is to use the ABS FPSO Eagle software to analyze the global strength including the rule check and direct strength analysis. And the same method can be adopted for the FPSO hull optimization by changing the depth. After calculation and optimization, the results are compared and analyzed. The results can be used as a reference for the future design or quotation purpose.

A flexible artificial solid-electrolyte interlayer supported by compactness-tailored carbon nanotube network for dendrite-free lithium metal anode

A dendrite-free lithium metal anode requires a stable interface designed for efficient and reversible lithium plating and stripping. In this work, we have devised a mechanically flexible artificial Li_(3)N solid-electrolyte interlayer supported by a dual-layer compactness-tailored carbon nanotube fiber network. The more compact side of the network ensures a full coverage of Li_(3)N, which prevents the reaction between electrolyte and lithium. The other side, with sparsely distributed nanotube fibers, provides mechanical flexibility for the film, and induces three-dimensional lithium deposition along its structure without any dendrite formation. The resulting full cell with NCM811 cathode has a high capacity retention of 95.1% for 160 cycles compared with less than 80% for the control.

刷状沙柳沙障固沙性能风洞模拟

与传统的沙柳沙障人工逐根布设不同,刷状沙柳沙障采用机械编织形成,有类似拒马的外形,布设后稳定性好,也便于施工。对一种以沙柳枝条为原料的刷状沙障固沙性能进行了风洞模拟。结果表明:(1)在第1道沙障前风速略有降低,在第1、2、4道沙障处,风速增加较大。在经过每道沙障后,风速下降较大,形成一个降速区。(2)沙障正下方沙面多表现为侵蚀状态。迎风的第1道沙障,侵蚀现象最严重,随着时间推移,甚至发生掏蚀现象。沙障之间多处于堆积状态,第1格堆积最严重,其后堆积程度减弱。(3)沙障设置后,风沙流结构呈复杂的指数下降曲线。8、12、16、20 m·s^(-1)风速下的集沙量分别减少86.8%、81.6%、53.4%、67.8%。这表明刷状沙柳沙障有较好的固沙性能。由于沙障的扰动,沙物质向上飘散,使地表10~14 cm高度以上进沙口的集沙量有所增加。

Mechanisms of the formation of wind-blown sand hazards and the sand control measures in Gobi areas under extremely strong winds along the Lanzhou-Xinjiang high-speed railway

The Lanzhou-Xinjiang high-speed railway(HSR)traverses areas of the Gobi Desert where extremely strong winds are frequent.These strong winds cause sand/gravel hazards,an unaddressed issue that often seriously compromises the safe operation of the HSR.This paper studies the mechanisms leading to wind-blown sand hazards and the outcomes of sand control projects in these areas.The main findings are as follows:(1)Cold northern airflows over the Tian Shan mountain range are accelerated by the wind tunnels and downslope effect as they pass over complex terrain comprising passes,gullies,and proluvial fans.Consequently,the wind intensity often increases two-to threefold,creating frequent high-speed winds that lead to severe sand damage along the HSR.(2)In the Gobi areas with extremely strong winds,sand grains can be lifted as high as 9 m from the ground into the air,far higher than in other areas of the desert.The sand transport rate decreases exponentially with increasing height.Both wind speed and particle size determine saltation height.Coarser particles and stronger winds provide the particles with a higher kinetic energy as they collide with the ground.In the wind zones of Baili and Yandun,the analysed study areas,the saltation layer height of wind-blown sand/gravel exceeds 3 and 2 m,respectively.(3)Based on the above findings,recently emerging sand control materials,suitable for the areas of interest,were screened and developed.Furthermore,under the proposed principle of‘supplementing blocking with trapping’,a comprehensive sand control measure was established,featuring sandblocking belts comprised of multiple rows,and high,vertical sand-trapping installations with a large grids size.The installed system showed a high efficacy,reducing sand transport rate by 87.87%and significantly decreasing the deposition of sand along a trial section of the HSR.

CVD growth of graphene on copper-plated scrap steel without external carbon source

Chemical vapor deposition(CVD)using gaseous hydrocarbon sources has shown great promise for large-scale graphene growth,but high growth temperatures(typically 1000℃)require sophisticated and expensive equipment,which increases graphene production costs.Here,we demonstrate a new approach to produce graphene at low cost from scrap steel sheets treated by thermal evaporation of copper plating,which is a derivative of traditional CVD technology.Without additional carbon sources,graphene film was successfully prepared on copper-coated scrap steel sheets at 820℃.The resulting graphene has few defects and uniform morphology,comparable to CVD graphene grown at 1000℃.Finally,the obtained graphene film is used in combination with an interdigital electrode to detect NO_(2)successfully,showing excellent performance.This technology expands the application of graphene in the manufacture of gas sensing devices and is compatible with traditional microelectronics technology.

气候变化对亚热带常绿阔叶林优势类群樟属植物的影响及保护评估

常绿阔叶林的优势类群由于其个体数量多、盖度大、生物量高、生存能力强,对维持相应生态系统的稳定起着主导作用。樟属(Cinnamomum)植物为亚热带常绿阔叶林的优势类群,通过对其过去、当前和未来潜在分布区的研究可以了解该类群的变迁历史,为理解亚热带常绿阔叶林动态变化提供帮助,有助于亚热带常绿阔叶林保育策略的制定。本研究利用最大熵(MaxEnt)模型模拟了我国樟属47种植物在5个时期(末次间冰期、末次盛冰期、全新世中期、当前和未来)的潜在分布区及物种丰富度热点区域。此外,根据樟属植物的物种丰富度热点区域与自然保护区相叠加,对当前自然保护区的保护状态进行了评估,尤其是为保护亚热带常绿阔叶林而设立的自然保护区。结果表明:樟属物种的潜在分布区在5个时期变化均不大,仅在亚热带–温带交界处的各大山脉和平原之间出现局部收缩和扩张;值得注意的是,物种丰富度热点区域在5个时期变化明显,末次盛冰期面积最大,相较于末次间冰期、全新世中期和当前分别多96%、88%和37%;未来(~2080年)两种不同温室气体排放典型浓度途径(representative concentration pathways,RCP)(RCP2.6和RCP8.5)下,樟属物种丰富度热点区域面积将分别比当前收缩8.4%和10.0%,并且随着温室气体排放的增加,物种热点区域收缩趋势会更加明显。此外,本研究发现樟属物种丰富度热点区域主要位于我国四川东南部、贵州南部、广西和广东,然而仅7.5%位于现有自然保护区内,未来自然保护区、国家公园等自然保护地的扩建、选址和规划应优先考虑四川东南部和华南地区。

非亲核镁硫电池电解液的研究进展

自从Muldoon课题组在2011年首次报道以[Mg_(2)(μ-Cl)_(3)(THF)_(6)]^(+)为阳离子电化学活性中心的非亲核有机铝镁盐用于镁硫电池以来,非亲核镁电解液便引起了人们的广泛关注.本文综述了非亲核镁电解质的合成、阳离子结构及其镁硫电池电解液电化学性能的研究进展.最后对非亲核镁硫电池电解液未来的发展方向进行了前瞻性的探讨,指出要推动镁硫电池的产业化,除了要开发高性能、低成本、结构简单的非亲核电解质材料以外,深入研究电解质盐及电解液组分与正/负电极材料最优匹配机制也至关重要.

mTOR regulates TLR-induced c-fos and Th1 responses to HBV and HCV vaccines

Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the existence of stringent regulatory mechanisms. In this study, we sought to uncover the mechanisms underlying TLR-induced IL-12 expression and the Th1 response. By systemic screening, we identified a number of protein kinases involved in the regulation of TLRinduced IL-12 expression. In particular, PI3 K, ERK, and m TOR play critical roles in the TLR-induced Th1 response by regulating IL-12 and IL-10 production in innate immune cells. Moreover, we identified c-fos as a key molecule that mediates m TOR-regulated IL-12 and IL-10 expression in TLR signaling. Mechanistically, m TOR plays a crucial role in c-fos expression, thereby modulating NFκB binding to promoters of IL-12 and IL-10. By controlling the expression of a special innate gene program, m TOR can specifically regulate the TLR-induced T cell response in vivo. Furthermore, blockade of m TOR by rapamycin efficiently boosted TLR-induced antigen-specific T and B cell responses to HBV and HCV vaccines. Taken together, these results reveal a novel mechanism through which m TOR regulates TLR-induced IL-12 and IL-10 production, contributing new insights for strategies to improve vaccine efficacy.

A non-nucleophilic gel polymer magnesium electrolyte compatible with sulfur cathode

Magnesium/sulfur battery(Mg/S)has recently received wide attention due to its high theoretical energy density(3,260 Wh/L)and low cost.To further improve its safety and flexibility,developing a polymer electrolyte that can be compatible with both electrophilic S and Mg is critical.Here,we report a magnesium chloride-(fluorinated tetraethylene glycolic)borate(MgCl-FTGB)based non-nucleophilic,gel-type polymer electrolyte for Mg/S battery via a facile synthetic method through commercially available reagents.This electrolyte coupled with glass fiber allows reversible Mg deposition/dissolution(100%coulombic efficiency)with low polarization(500μA/cm^2,300/300 mV),and shows a wide electrochemical window of 4.8 V(vs.Mg/Mg^2+).Mg/S battery assembled with this electrolyte can cycle over 50 times with a high specific discharge capacity retention of over 1,100 mAh/g.

An equine disease diagnosis expert system based on improved reasoning of evidence credibility

In China,there is a troubling shortage of well-trained equine veterinarians,leaving the needs of many equine farmers unmet.This is especially true with respect to the diagnosis of equine diseases.To solve this shortcoming,an equine disease diagnosis expert system was developed.For the aspect of knowledge representation,the structure of equine disease diagnosis knowledge was analyzed using an ontology system.Next,the clinical signs were described using an object-attribute-value(O-A-V)format,and the knowledge representation was then expressed using production rules.With respect to the reasoning mechanism,the weights of the clinical signs and promoted confidence factors(PCF)were combined to express information and rules pertaining to clinical signs with an associated level of uncertainty.The model was established based on improved reasoning of evidence credibility.Finally,using the ASP.Net platform and the SQL Server 2008 database,the equine disease diagnosis expert system based on the B/S structure has been developed,and is capable of reliably diagnosing 40 of the most common equine diseases.A functional evaluation of the system was conducted,and the diagnostic accuracy was observed to be 88%.This study demonstrates a bright prospect for the popularization and application of the system through continuous system maintenance and knowledge-based updates.

Synthesis, characterization and fluorescence quenching of conjugated polymer containing triphenylamine group

Poly(triphenylamine-p-phenylenevinylene)s with two different end-groups were obtained through a Wittig polycondensation.The structures of two copoly-mers were characterized.Ultraviolet and visible spectro-scopy(UV-Vis)and photoluminescence(PL)spectra show the end-capped polymer emits intensive green light in both solution and film state.Their applications in the detection of nitro compounds were investigated,and the results show high fluorescence quenching sensitivity of the end-capped polymer towards o-nitrotoluene(o-NT).When the concentration of o-NT was 21.5×10^(-3) mol/L,the fluorescence quenching reached 96%.Additionally,after the exposure of polymer film in three different quenchers such as dinitrotoluene(DNT),p-nitrobenzo-quinone(p-BQ)and p-nitrotoluene(p-NT)for 600 s,its fluorescence quenching reached 93.6%,11.5%and 77.9%,respectively.This kind of polymer has great advantages in preparation and may find applications in the detection of nitro explosives.

Monitoring and early warning system of porcine pasteurellosis based on WebGIS

The incidence of porcine pasteurellosis in China is so widespread that it is difficult to clearly understand the prevalence and maintain continuous monitoring.In order to reduce immense negative economic impact on the livestock industry;monitoring,early warning,and visual management systems are highly desirable.In this study,a monitoring and early warning systemfor porcine pasteurellosis was established based onWeb Geographical Information System(WebGIS)technology.By establishing a path analysis function,buffer analysis function,and hot spot analysis function,it can provide a method of support and control of infectious diseases.For early warning of disease,four common interpolation methods were tested,all of which showed that the affected area of porcine pasteurellosis in China was mainly concentrated in the south of the mainland.A cross-validation method was used to compare the four interpolation methods.The cross-validation showed that the inverse distance weighting(IDW)method was suitable for forecasting the occurrence of porcine pasteurellosis in China.Finally,using C sharp(C#)as the development language and WebGIS technology,a monitoring and early warning system based on Browser/Server structure was developed.This is the first monitoring and early warning system of porcine pasteurellosis based onWebGIS.The performance of theWebGIS technology indicated a great potential for animal infectious disease applications and provided a foundation for future work.