Pressure-induced growth of coralloid-like FeF_(2) nanocrystals to enable high-performance conversion cathode

Fluoride ferrous(FeF_(2))is viewed as a promising conversion cathode material for next-generation lithiumion batteries(LIBs)due to its high theoretical specific capacity and low cost.Unfortunately,issues such as poor intrinsic conductivity,iron dissolution,and phase separation hinder the application of FeF_(2)in highenergy cathodes.Here,a pressure-induced morphology control method is designed to prepare coralloidlike FeF_(2)nanocrystals with nitrogen-rich carbon coating(c-FeF_(2)@NC).The coralloid-like interconnected crystal structure of c-FeF_(2)@NC contributes to reducing interfacial resistance and enhancing the topotactic transformation during the conversion reaction,and the nitrogen-rich carbon(NC)coating can enhance interfacial stability and kinetic performance.When used as a conversion cathode for LIBs,c-FeF_(2)@NC exhibits a high initial reversible capacity of 503.57 mA h g^(-1)and excellent cycling stability of497.61 m A h g^(-1)with a low capacity decay of 1.19%over 50 cycles at 0.1 A/g.Even at 1 A/g,a stable capacity of 263.78 mA h g^(-1)can still be retained after 200 cycles.The capability of c-FeF_(2)@NC as a conversion cathode for sodium-ion batteries(SIBs)was also evaluated to expand its field of application.Furthermore,two kinds of full batteries have been assembled by employing c-FeF_(2)@NC as cathodes and quantitative limited-Li(LLi)and pre-lithiated reduced graphene oxide(PGO)as anodes,respectively,to envisage the feasibility of practical applications of conversion materials.

柱状金属锂沉积物:电解液添加剂的影响

二次电池的能量密度已成为推动电动汽车和便携式电子产品技术向前发展的重要指标。使用石墨负极的锂离子电池正接近其理论能量密度的天花板,但仍难以满足高端储能设备的需求。金属锂负极因其极高的理论比容量和极低的电极电位,受到了广泛关注。然而,锂沉积过程中枝晶的生长会导致电池安全性差等问题。电解液对金属锂的沉积有着至关重要的影响。本文设计了一种独特的电解槽体系来进行柱状锂的沉积,研究了不同电解液体系(1mol·L^(-1)LiPF6-碳酸乙烯酯/碳酸二乙酯(EC/DEC,体积比为1:1)、1 mol·L^(-1) LiPF6-氟代碳酸乙烯酯(FEC,体积分数5%)-EC/DEC (体积比为1:1))对金属锂沉积的影响。对两种电解液中金属锂沉积物长径比的研究表明,电解液的组分可以显著地影响金属锂的沉积形貌,在加入氟代碳酸乙烯酯(FEC)添加剂之后,柱状锂的直径从0.3–0.6μm增加到0.7–1.3μm,长径比从12.5下降到5.6。长径比的降低有助于减小金属锂和电解液的反应面积,提高金属锂负极的利用率和循环寿命。通过考察循环后锂片的表面化学性质,发现FEC的分解增加了锂表面固态电解质界面层中氟化锂(LiF)组分的比例,提高了界面层中锂离子的扩散速率,减少了锂的成核位点,从而给予锂核更大的生长空间,降低了沉积出的柱状锂的长径比。

Lithium–matrix composite anode protected by a solid electrolyte layer for stable lithium metal batteries

Lithium (Li) metal with an ultrahigh specific theoretical capacity and the lowest reduction potential is strongly considered as a promising anode for high-energy-density batteries. However, uncontrolled lithium dendrites and infinite volume change during repeated plating/stripping cycles hinder its practical applications immensely. Herein, a house-like Li anode (housed Li) was designed to circumvent the above issues. The house matrix was composed of carbon fiber matrix and affords a stable structure to relieve the volume change. An artificial solid electrolyte layer was formed on composite Li metal, just like the roof of a house, which facilitates uniform Li ions diffusion and serves as a physical barrier against electrolyte corrosion. With the combination of solid electrolyte layer and matrix in the composite Li metal anode, both dendrite growth and volume expansion are remarkably inhibited. The housed Li|LiFePO4 batteries exhibited over 95% capacity retention after 500 cycles at 1.0 C in coin cell and 85% capacity retention after 80 cycles at 0.5 C in pouch cell. The rationally combination of solid electrolyte layer protection and housed framework in one Li metal anode sheds fresh insights on the design principle of a safe and long-lifespan Li metal anode for Li metal batteries.

PD-1/PD-L1免疫检查点抑制剂在肺癌中的研究进展

近年来,免疫治疗的研究成果突出,多项临床试验捷报频传。目前,肺癌的免疫治疗研究已取得重大突破,特别是程序性死亡受体1(programmed death 1, PD-1)或程序性死亡配体1(programmed death-ligand 1,PD-L1)免疫检查点抑制剂(如Nivolumab、Pembrolizumab、Atezolizumab、Durvalumab和Avelumab等)在各项临床试验的成功应用,为包括鳞癌、腺癌和小细胞肺癌在内的多种病理类型肺癌患者均带来了临床获益。本文通过回顾并解读具有代表性的重要临床研究,全面分析PD-1/PD-L1免疫检查点抑制剂在肺癌中的应用价值和地位。基于各项大型临床试验的探索成果,肺癌免疫治疗细节正在不断优化,肺癌免疫治疗适应证也在不断拓宽。然而,免疫治疗仍面临很多挑战,例如免疫联合策略的选择、生物标志物的探索、不良反应的管理、驱动基因突变人群的应用可行性等等。本文就肺癌免疫治疗的最新重要进展作一系统综述,以期为广大临床工作者提供前沿参考。

Mesoporous Graphene Hosts for Dendrite-Free Lithium Metal Anode in Working Rechargeable Batteries

Lithium(Li) metal anode has received extensive attentions due to its ultrahigh theoretical capacity and the most negative electrode potential. However, dendrite growth severely impedes the practical applications of the Li metal anode in rechargeable batteries. In this contribution, a mesoporous graphene with a high specific surface area was synthesized to host the Li metal anode. The mesoporous graphene host(MGH) has a high specific surface area(2090 m^2/g), which affords free space and an interconnected conductive pathway for Li plating and stripping, thus alleviating the volume variation and reducing the generation of dead Li during repeated cycles. More importantly, the high specific surface area of MGH efficiently reduces the local current density of the electrode, which favors a uniform Li nucleation and plating behavior, rendering a dendritefree deposition morphology at a low overpotential. These factors synergistically boost the Li utilization(90.1% vs. 70.1% for Cu foil) and life span(150 cycles vs. 100 cycles for Cu foil) with a low polarization of MGH electrode at an ultrahigh current of 15.0 mA/cm^2. The as-prepared MGH can provide fresh insights into the electrode design of the Li metal anode operating at high rates.

Hierarchical nanostructured composite cathode with carbon nanotubes as conductive scaffold for lithium-sulfur batteries

Carbon nanotubes （CNTs） are excellent scaffolds for advanced electrode materials, resulting from their intrinsic sp2 carbon hybridization, interconnected electron pathway, large aspect ratio, hierarchical porous structures, and low cost at a large-scale production. How to make full utilization of the mass produced CNTs as building blocks for nanocomposite electrodes is not well understood yet. Herein, a composite cathode containing commercial agglomerated multi-walled CNTs and S for Li-S battery was fabricated by a facile melt-diffusion strategy. The hierarchical CNT@S coaxial nanocables exhibited a discharging capacity of 1020 and 740 mAh .g-1 at 0.5 and 2.0 C, respectively. A rapid capacity decay of 0.7% per cycle at the initial 10 cycles and a slow decay rate of 0.14% per cycle for the later 140 cycles were detected. Such hierarchical agglomerated CNT@ S cathodes show advantages in easy fabrication, environmentally benign, low cost, excellent scalability, and good Li ion storage performance, which are extraordinary composites for high performance Li-S battery.

Stable interfaces constructed by concentrated ether electrolytes to render robust lithium metal batteries

Lithium metal batteries(LMBs)are highly considered as promising candidates for next-generation energy storage systems.However,routine electrolytes cannot tolerate the high potential at cathodes and low potential at anodes simultaneously,leading to severe interfacial reactions.Herein,a highly concentrated electrolyte(HCE)region trapped in porous carbon coating layer is adopted to form a stable and highly conductive solid electrolyte interphase(SEI)on Li metal surface.The protected Li metal anode can potentially match the high-voltage cathode in ester electrolytes.Synergistically,this ingenious design promises high-voltage-resistant interfaces at cathodes and stable SEI with abundance of inorganic components at anodes simultaneously in high-voltage LMBs.The feasibility of this interface-regulation strategy is demonstrated in Li|LiFePO_(4) batteries,realizing a lifespan twice as long as the routine cells,with a huge capacity retention enhancement from 46.4%to 88.7%after 100 cycles.This contribution proof-ofconcepts the emerging principles on the formation and regulation of stable electrode/electrolyte interfaces in the cathode and anode simultaneously towards the next-generation high-energy-density batteries.

A novel strategy of lithium recycling from spent lithium-ion batteries using imidazolium ionic liquid

In light of the increasing demand for environmental protection and energy conservation,the recovery of highly valuable metals,such as Li,Co,and Ni,from spent lithium-ion batteries(LIBs)has attracted widespread attention.Most conventional recycling strategies,however,suffer from a lack of lithium recycling,although they display high efficiency in the recovery of Co and Ni.In this work,we report an efficient extraction process of lithium from the spent LIBs by using a functional imidazolium ionic liquid.The extraction efficiency can be reached to 92.5%after a three-stage extraction,while the extraction efficiency of Ni-Co-Mn is less than 4.0%.The new process shows a high selectivity of lithium ion.FTIR spectroscopy and ultraviolet are utilized to characterize the variations in the functional groups during extraction to reveal that the possible extraction mechanism is cation exchange.The results of this work provide an effective and sustainable strategy of lithium recycling from spent LIBs.

Attenuation characteristics of impact-induced seismic wave in deep tunnels:An in situ investigation based on pendulum impact test

The radiated seismic energy is an important index for the intensity assessment of microseismic(MS)events and the early warning of dynamic disasters.However,the energy of MS signals is significantly attenuated due to the heterogeneity and viscous damping of rock media.Therefore,the study on attenuation characteristics of MS signals in underground engineering has practical significance for the accurately estimation of radiated seismic energy.Based on a pendulum impact test facility and MS monitoring system,an in situ investigation was carried out to explore attenuation characteristics at a deep tunnel.The results show that the seismic energy and peak particle velocity(PPV)attenuation are exponentially related to the propagation distance.The attenuation coefficient of energy is larger than that of PPV.With the increase in the input impact-energy,the seismic energy attenuation coefficient decreases as a power function.An empirical relationship between energy attenuation coefficient and wave impedance of rock mass was established in this scenario.Moreover,the time-frequency characteristics and energy distribution laws of impact-induced signals were investigated by the continuous wavelet transform(CWT)and wavelet packet analyses,respectively.The dominant frequency of signals decreases gradually as the propagation distance increases.Based on the energy attenuation characteristics,a new method was proposed to calculate the released source energy of MS events in the field.This study can provide an insight into energy attenuation characteristics of seismic waves and references for attenuation correction in seismic energy calculation.

Three new species of Anthomedusae(Hydrozoa:Hydroidomedusa) from the Guangdong coastal water, China

The samples of Anthomedusae were collected from the Guangdong coastal water,China.Three new species of Anthomedusae,i.e.Zhangiella condensum Huang,Zhang et Sun,sp.nov.,Hydractinia leizhouensis Huang,Zhang et Yang,sp.nov.,and Cladosarsia simplex Huang,Zhang et Ke,sp.nov.are described.All type specimens are deposited in College of Ocean and Earth Sciences,Xiamen University.

Combination therapy with saxagliptin and vitamin D for the preservation ofβ-cell function in adult-onset type 1 diabetes:a multi-center,randomized,controlled trial

Disease modifying therapies aiming to preserveβ-cell function in patients with adult-onset autoimmune type 1 diabetes are lacking.Here,we conducted a multi-centre,randomized,controlled trial to assess theβ-cell preservation effects of saxagliptin alone and saxagliptin combined with vitamin D as adjunctive therapies in adult-onset autoimmune type 1 diabetes.In this 3-arm trial,301 participants were randomly assigned to a 24-month course of the conventional therapy(metformin with or without insulin)or adjunctive saxagliptin or adjunctive saxagliptin plus vitamin D to the conventional therapy.The primary endpoint was the change from baseline to 24 months in the fasting C-peptide.The secondary endpoints included the area under the concentration-time curve(AUC)for C-peptide level in a 2-h mixed-meal tolerance test,glycemic control,total daily insulin use and safety,respectively.The primary endpoint was not achieved in saxagliptin plus vitamin D group(P=0.18)and saxagliptin group(P=0.26).However,compared with the conventional therapy,2-h C-peptide AUC from 24 months to baseline decreased less with saxagliptin plus vitamin D(-276 pmol/L vs.-419 pmol/L;P=0.01),and not to the same degree with saxagliptin alone(-314 pmol/L;P=0.14).Notably,for participants with higher glutamic acid decarboxylase antibody(GADA)levels,the decline ofβ-cell function was much lower in saxagliptin plus vitamin D group than in the conventional therapy group(P=0.001).Insulin dose was significantly reduced in both active treatment groups than in the conventional therapy group despite all groups having similar glycemic control.In conclusion,the combination of saxagliptin and vitamin D preserves pancreaticβ-cell function in adult-onset autoimmune type 1 diabetes,an effect especially efficacious in individuals with higher GADA levels.Our results provide evidence for a novel adjunct to insulin and metformin as potential initial treatment for adult-onset type 1 diabetes.(ClinicalTrials.gov identifier:NCT02407899).

我国网络文学海外阅读发展现状、困境与对策分析——基于“起点国际”平台的考察

网络文学是数字出版和数字阅读行业的重要组成部分,在数字经济和文化强国战略推动下,我国网络文学国际影响力不断提高,海外阅读迎来重大发展机遇.论文基于对海外阅读平台"起点国际"的参与式观察,揭示了我国网络文学海外阅读的发展现状,从作品类型、翻译质量、平台运营机制等角度分析了其发展困境,同时提出了基于海外读者阅读需求开发定制化、国际化网络文学作品,统筹个体、团队、技术资源提升网络文学翻译效能,借鉴国内网络文学平台运营机制和全产业链出版模式探索融合发展等3个方面的对策建议,为网络文学海外阅读高质量发展和中华优秀文化国际传播提供理论智慧.

Integrated lithium metal anode protected by composite solid electrolyte film enables stable quasi-solid-state lithium metal batteries

Lithium(Li) metal,possessing an extremely high theoretical specific capacity(3860 mAh/g) and the most negative electrode potential(-3.040 V vs.standard hydrogen electrode),is one the most favorable anode materials for future high-energy-density batteries.However,the poor cyclability and safety issues induced by extremely unstable interfaces of traditional liquid Li metal batteries have limited their practical applications.Herein,a quasi-solid battery is constructed to offer superior interfacial stability as well as excellent interfacial contact by the incorporation of Li@composite solid electrolyte integrated electrode and a limited amount of liquid electrolyte(7.5 μL/cm2).By combining the inorganic garnet Aldoped Li6.75La3Zr1.75Ta0.25O12(LLZO) with high mechanical strength and ionic conductivity and the o rganic ethylene-vinyl acetate copolymer(EVA) with good flexibility,the composite solid electrolyte film could provide sufficient ion channels,sustained interfacial contact and good mechanical stability at the anode side,which significantly alleviates the thermodynamic corrosion and safety problems induced by liquid electrolytes.This innovative and facile quasi-solid strategy is aimed to promote the intrinsic safety and stability of working Li metal anode,shedding light on the development of next-generation highperformance Li metal batteries.

Binder-Free Activated Carbon/Carbon Nanotube Paper Electrodes for Use in Supercapacitors

新奇便宜、轻、灵活、平的 rollup 或便携设备为多功能的便携式的电子学被要求并且作为在当代的电池和 supercapacitors 使用的材料的选择开发新万用、灵活的电极材料是关键挑战。这里，为在先进 supercapacitors 的使用的没有文件夹的激活的碳(交流)/carbon nanotube (CNT ) 纸电极基于便宜、工业等级的排列 CNT 被制作了。由砍的一个二拍子的圆舞策略，排列 CNT 被驱散进单个长 CNT，然后交流的 90 wt%99 wt% 粉末被合并到 CNT 肉和 AC/CNT 纸电极被免职在一个过滤器上制作。AC/CNT 纸电极的特定的能力，率表演，和力量密度比对一个交流 / 乙炔黑人电极的相应价值好。电容到达了 267.6 F/g 的最大的价值， CNT 5 wt% 装载，并且精力密度和功率密度是 22.5

Recent advances in energy chemistry of precious-metal-free catalysts for oxygen electrocatalysis

The oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) are coupled with various sustainable energy systems and are significant for the future energy scenario. Both of them suffer from sluggish kinetics, which calls for cost-effective and high-performance electrocatalysts to promote. The oxygen electrolysis of OER and ORR is heterogeneous reaction, which involves reactant and electron transfer, and a serial of complicate surface reactions. Both intrinsic catalyst activity and extrinsic physicochemical characters play a vital role in overall electrocatalytic reactivity. Herein. recent advances in rational design and effective construction of precious-metal-free materials are reviewed for OER and ORR, respectively, in the respects of electronic structure regulation, nanostructure tailor, and freestanding electrode fabrication. The reaction mechanism of OER and ORR are also updated. This review provides emerging energy chemistry concepts and materials chemistry strategies of electrocatalysts for OER and ORR, which is also enlightening for other energy conversion devices with targeted optimization.

Process Intensifi cation by CO_(2)for High Quality Carbon Nanotube Forest Growth:Double-Walled Carbon Nanotube Convexity or Single-Walled Carbon Nanotube Bowls?

Introduction of CO_(2)is a facile way to tune the growth of vertically aligned double-or single-walled carbon nanotube(CNT)forests on wafers.In the absence of CO_(2),a double-walled CNT convexity was obtained.With increasing concentration of CO_(2),the morphologies of the forests transformed first into radial blocks,and finally into bowl-shaped forests.Furthermore,the wall number and diameter distribution of the CNTs were also modulated by varying the amount of CO_(2).With increasing CO_(2)concentration,CNTs with fewer wall number and smaller diameter were obtained.The addition of CO_(2)is speculated to generate water and serve as a weak oxidant for high quality CNT growth.It can tune the growth rate and the morphologies of the forests,prevent the formation of amorphous carbon,and reduce the wall number of the CNTs.

Taxonomic notes on Hydroidomedusae (Cnidaria) from South China Sea Ⅲ： Family Rathkeidae and Zancleopsidae

This study reviews all South China Sea species belonging to the families Rathkeidae and Zancleopsidae. Morphological characters of Lizzia blondina Forbes, 1848 （formerly recorded as Podocoryne/Hydractinia minuta）, L. gracilis （Mayer, 1900）, L. octostyla （Haeckel, 1879） and Podocorynoides minima （Trinci, 1903） （formerly recorded as Podocoryne/ Hydractinia minima） are redescribed. One new species, Zancleopsis oblongus Xu, Huang ＆ Wang, sp. nov. from South China Sea, is described and illustrated. The keys to all medusa genera of Rathkeidae and Zancleopsidae and to all species of Zancleopsis are presented. The type specimen is deposited in the Third Institute of Oceanography, State Oceanic Administration, China.

Taxonomic notes on Hydroidomedusae (Cnidaria) from South China Sea I：Family Eucodoniidae (Anthomedusae)

A generic diagnosis of family Eucodoniidae is revised, with the monotype genus Eucodonium. Three new species, Eucodonium bitentaculatum Xu, Huang ＆ Guo, sp. nov., E. brevistyle Xu, Huang ＆ Lin, sp. nov. and E. longitentaculatum Xu, Huang ＆ Wang, sp. nov. from South China Sea are described and illustrated. A key to all species of Eucodonium is provided. The type specimens are deposited in the Third Institute of Oceanography, State Oceanic Administration.

Two-dimensional vermiculite separator for lithium sulfur batteries

Lithium-sulfur batteries have been considered as one of the most promising battery system for their high theoretical energy density. However, the lithium-sulfur batteries suffer from the dissolution and diffusion of polysulfides, which induce parasitic reactions with lithium metal anodes. The safety of lithium-sulfur batteries is also concerned with the risk of dendrite growth on lithium metal anodes. To simultaneously address the challenges in the shuttle effect and safety problems, we demonstrate herein a two-dimensional vermiculite separator. With the assembly of the 2D exfoliated vermiculite sheets, the vermiculite separator can suppress the diffusion of polysulfides across the separator through electrostatic interaction and steric hindrance. Meanwhile, the inorganic sheets with high strength and Young＇s modulus prevent the penetration of lithium metal dendrite and potentially improve the safety of the system. This work elucidates a promising strategy for safe and stable lithium sulfur batteries, and can also be extended to other electrochemical systems based on metal anodes.

Some new Hydroidomedusa(Cnidaria) from the northern South China Sea

The study reviews all medusa genera and species belonging to the families Bougainvilliidae, Eucodoniidae, Proboscidactylidae, Corymorphidae and Sugiuridae from the northern South China Sea. A new genus Xu, Guo & Wang, gen. nov. is erected under the family Sugiuridae, based on the monotype, Monocanna ovale(Mayer, 1900) comb. nov. from Gastroblasta. Four new species, Nubiella terminaliknoba Xu, Guo & Wang sp. nov., Paranubiella shenzhenensis Xu, Huang & Wang, sp. nov., Eucodonium crassonemalis Xu, Guo & Lin, sp. nov. and Proboscidactyla trifurcata Xu, Huang & Guo, sp. nov., are described and illustrated here. The species Euphysora knides Huang, 1999 stat. rev. is revised to be a valid species. The keys to known genera of families Corymorphidae, Sugiuridae and species of genera Paranubiella, Eucodonium, Proboscidactyla are provided. All type specimens are deposited in the College of Ocean and Earth Sciences, Xiamen University.