Heterostructured Mn_(3)O_(4)-MnS Multi-Shelled Hollow Spheres for Enhanced Polysulfide Regulation in Lithium-Sulfur Batteries

Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and sluggish kinetics of polysulfide in lithium-sulfur(Li-S)batteries.However,a single strategy can only take limited effect.Modulating catalytic hosts with synergistic effects are urgently desired.Herein,Mn_(3)O_(4)-MnS heterogeneous multi-shelled hollow spheres are meticulously designed by controlled sulfuration of Mn2O3 hollow spheres,and then applied as advanced encapsulation hosts for Li-S batteries.Benefiting from the separated spatial confinement by hollow multi-shelled structure,ample exposed active sites and built-in electric field by heterogeneous interface,and synergistic effects between Mn_(3)O_(4)(strong adsorption)and MnS(fast conversion)components,the assembled battery achieves prominent rate capability and decent cyclability(0.016%decay per cycle at 2 C,1000 cycles).More crucially,satisfactory areal capacity reaches up to 7.1 mAh cm^(-2)even with high sulfur loading(8.0 mg cm^(-2))and lean electrolyte(E/S=4.0 pL mg^(-1))conditions.This work will provide inspiration for the rational design of hollow multi-shelled heterostructure for various electrocatalysis applications.

Stable immobilization of lithium polysulfides using three-dimensional ordered mesoporous Mn_(2)O_(3) as the host material in lithium-sulfur batteries

Lithium-sulfur batteries(LSBs)have drawn significant attention owing to their high theoretical discharge capacity and energy density.However,the dissolution of long-chain polysulfides into the electrolyte during the charge and discharge process(“shuttle effect”)results in fast capacity fading and inferior electrochemical performance.In this study,Mn_(2)O_(3)with an ordered mesoporous structure(OM-Mn_(2)O_(3))was designed as a cathode host for LSBs via KIT-6 hard templating,to effectively inhibit the polysulfide shuttle effect.OM-Mn_(2)O_(3)offers numerous pores to confine sulfur and tightly anchor the dissolved polysulfides through the combined effects of strong polar-polar interactions,polysulfides,and sulfur chain catenation.The OM-Mn_(2)O_(3)/S composite electrode delivered a discharge capacity of 561 mAh g^(-1) after 250 cycles at 0.5 C owing to the excellent performance of OM-Mn_(2)O_(3).Furthermore,it retained a discharge capacity of 628mA h g^(-1) even at a rate of 2 C,which was significantly higher than that of a pristine sulfur electrode(206mA h g^(-1)).These findings provide a prospective strategy for designing cathode materials for high-performance LSBs.

Influence of Sowing Season and Host Crop Identity on the Community Structure of Arbuscular Mycorrhizal Fungi Colonizing Roots of Two Different Gramineous and Leguminous Crop Species

Introduction of cover crops may improve the diversity of arbuscular mycorrhizal fungi (AMF) in roots and soil under crop rotational systems;therefore, it is necessary to determine the potential for AMF communities to improve sustainable food production. We investigated the impact of cover crops, including wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), pea (Pisum sativum L.), and hairy vetch (Vicia villosa Roth.), on the AMF communities in their roots in autumn and spring sowing seasons with PCR-DGGE analysis. Although all four cover crops impacted the AMF community structure in roots, the diversity of AMF communities was unchanged among crop type or sowing season. Redundancy analysis (RDA) demonstrated that AMF communities within crop type were significantly different. However, the AMF community structures were not influenced by growing season, suggesting that growth stage in crops may be more responsive to shaping AMF community structure in crop roots than host crop identity.

Atomistic Simulation Study of Defect Structure of Zircon as a High-Level Nuclear Waste Host Form

A set of potential parameters for modeling zircon was obtained by atomistic simulation techniques and a reasonable structural model of zircon was established by fitting some important properties of zircon.Based on the equilibrium configuration of zircon, authors calculated the formation energies of basic point defects and intrinsic disorders. The heats of solution of substituting Pu for Zr showed that there was an immiscible gap at the composition of (Pu75%-Zr25%, in mole fraction), which suggests that the amount of Pu substituting for Zr in zircon be≤50%.

Structure engineering of cathode host materials for Li-S batteries

Although lithium-sulfur batteries are one of the favorable candidates for next-generation energy storage devices,a few key challenges that have not been addressed have limited its commercialization.These challenges include lithium dendrite growth in the anode side,volume change of the active material,poor electrical conductivity,dissolution and migration of poly sulfides,and slow rate of solid-state reactions in the cathode side.Since the electrochemical performance of lithium-sulfur batteries is greatly affected by the design of the cathode host material,it has also been widely discussed in addressing the abovementioned issues.In this paper,three design ideas of cathode host materials in terms of microstructure,crystal structure and electronic structure are introduced and summarized.Crucially,the current progress of these three structural design strategies and their effects on the electrochemical performance of lithium-sulfur batteries are discussed in detail.Finally,future directions in the structural design of cathode materials for lithium-sulfur batteries are discussed and further perspectives are provided.

Stabilizing lithium deposition within bimodal porous SiO_(2)-TiO_(2) microspheres as 3D host structure

Three-dimensional (3D) host materials for lithium metal anodes (LMAs) have gained attention because they can mitigate volume expansion and local current density through their large surface area and suppress the dendritic growth of lithium. Recent research on 3D host materials has focused on conductive materials;however, the benefits of 3D host materials cannot be fully utilized because lithium deposition begins at the top of the structure. Herein, we fabricate SiO_(2)-TiO_(2) composite microspheres with bimodal pore structures (bi-SiTiO) by simple spray pyrolysis. These microspheres effectively store lithium within the structure from the bottom of the electrode while preventing lithium dendrite formation. Focused ion beam-scanning transmission electron microscopy (FIB-STEM) analysis reveals that the lithiophilic properties of composite microspheres enhanced their effectiveness in storing lithium, with small pores acting as “lithium-ion sieves” for a uniform lithium-ion flux and large pores that provide sufficient volume for lithium deposition. The bi-SiTiO composite microspheres exhibit a high Coulombic efficiency of 98.5% over 200 cycles at 2.0 mA·cm^(−2) when operated in a lithium half-cell. With a high lithium loading of 5.0 mAh·cm^(−2), the symmetrical cell of the bi-SiTiO electrode sustains more than 900 h. A full cell coupled with an LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) (NCM811) cathode also exhibits enhanced electrochemical properties in terms of cycling stability and rate capability.

Multi‑omics reveals that the host‑microbiome metabolism crosstalk of differential rumen bacterial enterotypes can regulate the milk protein synthesis of dairy cows

Background Dairy cows’lactation performance is the outcome of the crosstalk between ruminal microbial metabo-lism and host metabolism.However,it is still unclear to what extent the rumen microbiome and its metabolites,as well as the host metabolism,contribute to regulating the milk protein yield(MPY).Methods The rumen fluid,serum and milk of 12 Holstein cows with the same diet(45%coarseness ratio),parity(2–3 fetuses)and lactation days(120–150 d)were used for the microbiome and metabolome analysis.Rumen metabolism(rumen metabolome)and host metabolism(blood and milk metabolome)were connected using a weighted gene co-expression network(WGCNA)and the structural equation model(SEM)analyses.Results Two different ruminal enterotypes,with abundant Prevotella and Ruminococcus,were identified as type1 and type2.Of these,a higher MPY was found in cows with ruminal type2.Interestingly,[Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae(the differential bacteria)were the hub genera of the network.In addition,differential ruminal,serum and milk metabolome between enterotypes were identified,where the cows with type2 had higher L-tyrosine of rumen,ornithine and L-tryptophan of serum,and tetrahydroneopterin,palmitoyl-L-carnitine,S-lactoylglutathione of milk,which could provide more energy and substrate for MPY.Further,based on the identi-fied modules of ruminal microbiome,as well as ruminal serum and milk metabolome using WGCNA,the SEM analysis indicated that the key ruminal microbial module1,which contains the hub genera of the network([Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae)and high abundance of bacteria(Prevotella and Ruminococcus),could regulate the MPY by module7 of rumen,module2 of blood,and module7 of milk,which contained L-tyrosine and L-tryptophan.Therefore,in order to more clearly reveal the process of rumen bacterial regulation of MPY,we established the path of SEM based on the L-tyrosine,L-tryptophan and related components.The SEM based on the metabolites suggested that[Ruminococcus]gauvreauii group could inhibit the energy supply of serum tryptophan to MPY by milk S-lactoylglutathione,which could enhance pyruvate metabolism.Norank_f_Ruminococcaceae could increase the ruminal L-tyrosine,which could provide the substrate for MPY.Conclusion Our results indicated that the represented enterotype genera of Prevotella and Ruminococcus,and the hub genera of[Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae could regulate milk protein synthesis by affecting the ruminal L-tyrosine and L-tryptophan.Moreover,the combined analysis of enterotype,WGCNA and SEM could be used to connect rumen microbial metabolism with host metabolism,which provides a fundamental understanding of the crosstalk between host and microorganisms in regulating the synthesis of milk composition.

One and Two-dimensional Structures of a New Oxamido Copper(II) Complex with Phthalato Bridged

A new o-phthalato-bridged oxamide copper（Ⅱ） complex 1, {[Cu2（oxap）]（pht）. 4H2O}n （oxap=N, N＇-bis（2-aminopropyl）oxamide, pht= phthalate dianion）, has been prepared and structurally characterized. It crystallizes in monoclinic, space group C2/c with a=23.424（4）, h=7.9696（14）, c=15.727（3）A°,β=129.617（2）°, C16H28Cu2N4O10, Mr=563.50, V=2261.6（7） A°, Z=4, Dc=1.655 g/cm^3, μ（MoKα）=1.939 mm^-1, F（000） = 1160, the final R=0.0393 and wR=0.0928 for 1707 observed reflections with I〉2σ（1）. Single-crystal X-ray analysis reveals that 1 displays a one-dimensional zigzag chain structure, in which each Cu（oxap） moiety adopting trans-conformation is connected by ,μ1,6-phthalate anion bridges, and these zigzag chains are further linked by another ,μ1,6-phthalate anion bridge to form a 2D sheet structure. The polar guest water molecules reside in the inter-and intrasheets to stabilize the whole crystal structure.

大赋用经:主客结构与铺陈考量

《文心雕龙·诠赋》谓“遂客主以首引,极声貌以穷文”,前者是汉大赋主客问答的框架结构,后者则是在此框架结构下预设的铺陈空间,铺陈乃是大赋的主体。主客问答以议论显示讽谏,多用经语。大赋中除直接铺陈仪礼的段落,铺陈则用经为寡。然班固《东都赋》、张衡《东京赋》等则以议论充塞铺陈空间,又大赋短制如扬雄《河东赋》全篇以议论为主,相对于大赋铺陈主体,并用经为多。但大赋绝大部分的铺陈取于六经之外的其他典籍,亦多语词自造。总体而言,汉赋用经为少,而且赋体铺陈所取于六经及其他典籍者,都用以夸饰铺陈,并不保留其在原初文本的意义,故不必说是“经学影响”。

基于ISP1161的嵌入式USB-HOST技术研究

介绍了USB(UniversalSerialBus,通用串行总线)协议的拓扑结构和软件结构,引入了专门用以在嵌入式系统或便携式设备中实现USB协议的芯片ISP1161,介绍了其硬件结构,,尤其重点分析完成USB协议所必需的寄存器状态,并给出了在嵌入式系统中利用ISP1161实现USBHOST(USB主协议)的软件流程,最后,列举了应用该USBHOST模块的嵌入式系统的的实例。

嵌入式系统中实现USB HOST技术研究

USB协议由于不对称,使嵌入式系统实现USB HOST协议比较困难,ISP1161的出现改变了这种状况。简要介绍了USB协议的拓扑结构和软件结构,重点分析了ISP1161的硬件结构,并给出在嵌入式系统中利用ISP1161实现USB HOST的软件流程,最后,给出了应用USB HOST模块的实例。

Update on enteroviral protease 2A:Structure,function,and host factor interaction

Enteroviruses(EVs)are human pathogens commonly observed in children aged 0–5 years and adults.EV infections usually cause the common cold and hand-foot-and-mouth disease;however,more severe infections can result in multiorgan complications,such as polio,aseptic meningitis,and myocarditis.The molecular mechanisms by which enteroviruses cause these diseases are still poorly understood,but accumulating evidence points to two enterovirus proteases,2Apro and 3Cpro,as the key players in pathogenesis.The 2Apro performs post-translational proteolytic processing of viral polyproteins and cleaves several host factors to evade antiviral immune responses and promote viral replication.It was also discovered that coxsackievirus-induced cardiomyopathy was caused by 2Apro-mediated cleavage of dystrophin in cardiomyocytes,indicating that cellular protein proteolysis may play a key role in enterovirus-associated diseases.Therefore,studies of 2Apro could reveal additional substrates that may be associated with specific diseases.Here,we discuss the genetic and structural properties of 2Apro and review how the protease antagonizes innate immune responses to promote viral replication,as well as novel substrates and mechanisms for 2Apro.We also summarize the current approaches for identifying the substrates of 2Apro to discover novel mechanisms relating to certain diseases.

广东省广宁县丰木地区金矿地质特征及找矿标志

丰木地区金矿床位于粤西广宁县北部,黄泥坑金矿床的南西部。区内多期次岩浆活动,断裂构造发育,具有良好的构造蚀变岩型金多金属矿床的成矿条件。本文对丰木地区金矿区的地质特征进行研究,判断其为剪切带控制的中低温热液金矿床,并总结了找矿标志,为下一步勘查提供依据。

煤矿用TBM主机带式输送机自适应随动结构的研究

针对煤矿用硬岩隧道掘进机(TBM)主机带式输送机的结构形式难以满足对其在推进、截割、上下坡、水平转弯、纠偏及换步等运行工况下实现小转弯半径的特殊要求的问题,提出了基于自适应随动结构的TBM主机带式输送机工作原理。该结构不仅解决了小直径TBM因内部空间小无法采用2部带式输送机上下搭接转载结构的问题,而且对大直径TBM也具有占用空间小、成本低、运行过程中粉尘污染小及噪声低等优点,有较高推广应用价值。

Avian hepatitis B viruses： Molecular and cellular biology, phylogenesis, and host tropism

The human hepatitis B virus （HBV） and the duck hepatitis B virus （DHBV） share several fundamental features. Both viruses have a partially double-stranded DNA genome that is replicated via a RNA intermediate and the coding open reading frames （ORFs） overlap extensively. In addition, the genomic and structural organization, as well as replication and biological characteristics, are very similar in both viruses. Host of the key features of hepadnaviral infection were first discovered in the DHBV model system and subsequently confirmed for HBV. There are, however, several differences between human HBV and DHBV. This review will focus on the molecular and cellular biology, evolution, and host adaptation of the avian hepatitis B viruses with particular emphasis on DHBV as a model system.

A New Series of Charge-assisted Hydrogen-bonded Host Frameworks Based on [Co(en)_3]^(3+)and Dicarboxylates

A new series of metal complex carboxylates（MCC）made of [Co（en）3]3＋（MC）and either 2,6-naphthalenedicarboxylic（NDC）or 4,4-biphenyldicarboxylic（BPDC）were synthesized and structurally characterized.The four new compounds have a general formula（MC）2（C）3·n（guest）with the guests of dimethylformamide（DMF）and dimethyl sulfoxide（DMSO）and water.All the structures represent a pillared-layer type,where the layer consists of MC cations,carboxylate anions or water molecules via a large number of hydrogen bonds.The layers are pillared by the organic residues of NDC or BPDC,resulting in the inclusion cavities where the guest molecules reside.Although their topological structures are similar,they crystallize in different crystal structures due to the rearrangement of pillars and hydrogen-bonded layers.

基于Workbench-AQWA的铺管船托管架结构时程分析

选择上海振华重工设计制造的用于铺设海底管道铺管船托管架作为研究对象,通过AQWA软件得到铺管船与托管架的运动响应幅值算子(RAO),并通过时域分析计算铺管船与托管架在实际海况下的波浪载荷和加速度时程;采用OFFPIPE软件对不同管径、水深的管道-托管架模型(线-点模型)进行动态铺设分析并得到托辊反力;根据托管架受载的特点,以加速度时程作为托管架的载荷条件对其进行结构时程分析,对比在规则波与不规则波海况下的应力水平。研究成果为后续托管架设计奠定基础。

东昆仑五龙沟金成矿系统:基本特征、成矿控制与勘查标志

五龙沟金矿田位于东昆仑造山带东段,金成矿与三叠纪岩浆作用、脆性和/或韧性变形显示密切时空联系。但是,金容矿地质体类型与控矿构造特征尚不清,金成矿受哪些关键要素控矿尚不明确。本文通过广泛深入的文献资料调研与详细的野外调查,详细阐明了五龙沟地区金矿床地质特征与成矿地质环境,系统梳理、总结与对比了不同地段金矿床的矿化类型、容矿地质体与控矿构造。研究表明,五龙沟金矿田发育微细脉型、蚀变岩型、石英脉型等3种矿化类型,容矿地质体主要以元古界—奥陶系变质岩系与侵入岩类为主。早期韧性剪切作用导致矿源层中金的活化与预富集,金矿化主要受控于晚期北西向脆性变形及相关断裂破碎带。大规模金成矿与古特提斯洋关闭及伴随的同/后碰撞构造过程有关。北西向构造—蚀变带、侵入岩类与古老变质基底是五龙沟金矿田的重要勘查标志。

基于光伏重心理论的配电网分布式光伏最大准入容量计算

随着高比例分布式光伏的接入,配电网分布式光伏最大准入容量(hosting capacity,HC)的确定成为了业界关注的焦点。提出了矩和重心的概念,并通过理论分析得到光伏重心必须超前于负荷重心的全局度量指标(globalmetric,GM)。继而推导了满足节点电压越上限约束和线路载流量约束的非迭代的HC的解析表达式,分别得到了节点电压和载流量度量指标LM1、LM2,它们与GM一起构成了完整的光伏重心理论。在此基础上,提出了配电网分布式光伏最大准入容量的新算法和修正算法,修正算法能考虑已有光伏接入和可开发光伏容量等现场约束。IEEE 33算例表明,与考虑无功分布和线损的经典蒙特卡洛算法相比,所提方法在准确性较好的同时,计算效率极高、且能兼顾已有光伏接入和可开发光伏容量等实际限制,工程实用性强。

动物内寄生虫丝氨酸蛋白酶研究进展

丝氨酸蛋白酶(serine proteases)是一类以丝氨酸为活性中心的蛋白水解酶,参与动物机体的蛋白质代谢、消化、凝血、发育调节和受精等生理过程,具有重要的生物学研究和应用价值。动物内寄生虫丝氨酸蛋白酶参与虫体营养、发育、宿主入侵、免疫反应和抗凝等生物学过程,在寄生虫寄生生活及其宿主相互作用中发挥着重要的作用。鉴于目前动物内寄生虫丝氨酸蛋白酶的相关研究缺乏系统性归纳和总结,拟对动物内寄生虫的丝氨酸蛋白酶研究现状及其在寄生虫-宿主互作中的生物学功能进行概述,以期为寄生虫丝氨酸蛋白酶的进一步研究提供信息参考。