Rationally designing electrolyte additives for highly improving cyclability of LiNi_(0.5)Mn_(1.5)O_(4)/Graphite cells

High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries.

科学可视化应用于药物分析实验教学——以葡萄糖的鉴别为例

以葡萄糖鉴别为例,讲述了将科学可视化引入药物分析实验的教学设计和视频制作流程。以图片和视频的方式,形象生动地展示了实验原理、操作过程和实验现象,增加了课程的趣味性和吸引力。拍摄制作的一系列相关视频已应用于课堂教学并发布于视频网站,取得了较好的教学效果,并实现了更大范围的共享和交流。

Mild hypothermia effects on matrix metalloproteinase-9 expression in the perihematomal region of rats following experimental intracerebral hemorrhage

BACKGROUND： Matrix metalloproteinase-9 （MMP-9） expression increases with intracerebral hemorrhage, and participates in the pathophysiological processes of secondary brain injury after intracerebral hemorrhage. OBJECTIVE： To investigate the effects of mild hypothermia on MMP-9 expression and brain edema in the perihematomal region of experimental intracerebral hemorrhage rats. DESIGN, TIME AND SETTING： The randomized, controlled experiment was performed at the Central Laboratory of Shandong Provincial Hospital between May and September 2007. MATERIALS： Seventy-two, Wistar, male rats, 12-weeks old, were used for this study. Rabbit anti-MMP-9 primary antibody was purchased from Boster, China. METHODS： Wistar rats were equally and randomly divided into normothermia and mild hypothermia groups. The two groups each comprised control, 6-hour intracerebral hemorrhage, 24-hour intracerebral hemorrhage, 48-hour intracerebral hemorrhage, 72-hour intracerebral hemorrhage, and l-week intracerebral hemorrhage subgroups, with six rats in each subgroup. Rat models of intracerebral hemorrhage were established by injecting 100 μL of autologous blood into the rat caudate nucleus. Rats in the mild hypothermia group received four hours of local mild hypothermia immediately following the injection. lntracerebral temperature was maintained at （33 ± 0.5） ℃. Subsequently, intracerebral temperature was spontaneously recovered at 25 ℃. Rats in the control subgroup were not injected with autologous blood and received only with intracerebral hemorrhage. MAIN OUTCOME MEASURES： Brain water content and MMP-9 expression surrounding the hematoma region. RESULTS： MMP-9 expression increased at 6 hours, and brain edema reached a peak at 48 hours after intracerebral hemorrhage. MMP-9 expression was significantly decreased in the mild hypothermia group compared with the normothermia group at each time point （P 〈 0.05）. CONCLUSION： Mild hypothermia can significantly inhibit MMP-9 overexpression and relieve brain edema following intracerebral hemorrhage.

Innovative discontinuous-SEI constructed in ether-based electrolyte to maximize the capacity of hard carbon anode

Compared with graphite,the lower sodiation potential and larger discharge capacity of hard carbon(HC)makes it the most promising anode material for sodium-ion battery.Utilizing ether-based electrolyte rather than conventional carbonate-based electrolyte,HC achieves superior electrochemical performance.Nevertheless,the mechanism by which ether-based electrolyte improves the properties of HC is still controversial,primarily focusing on whether it forms solid electrolyte interphase(SEI)film.In this work,according to the sodium storage mechanisms in HC at low voltage(<0.1 V),including Na^(+)-diglyme co-interaction into the carbon layer(SEI forbidden)and desolvated Na^(+)insertion in the irregular carbon holes(SEI required),the NaPF6concentration in ether-based electrolyte was regulated,so as to construct a discontinuous-SEI on the surface of the HC anode,which significantly enhances the electrochemical performances of HC.Specifically,with 0.2 M NaPF6ether-based electrolyte,HC deliverers a discharge capacity of 459.7 mA h g^(-1)at 0.1 C and stays at 357.2 mA h g^(-1)after 500 cycles at 1 C,which is substantially higher than that of higher/lower salt concentration electrolytes.

Highly improved cyclic stability of Ni-rich/Li batteries with succinic anhydride as electrolyte additive and underlying mechanism

Lithium-metal battery based on Ni-rich cathode provides high energy density but presents poor cyclic stability due to the unstable electrode/electrolyte interfaces on both cathode and anode.In this work,we report a new strategy to address this issue.It is found that the cyclic stability of Ni-rich/Li battery can be significantly improved by using succinic anhydride(SA) as an electrolyte additive.Specifically,the capacity retention of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)/Li cell is improved from 14% to 83% after 200cycles at 1 C between 3.0 and 4.35 V by applying 5% SA.The underlying mechanism of SA contribution is understood by comparing the effects of malic anhydride(MA) and citraconic anhydride(CA), both of which share a similar molecular structure to SA but show different effects.On anode side,SA can but MA and CA cannot form a protective solid electrolyte interphase(SEI) on Li anode.On cathode side,three anhydrides can suppress the formation of hydrogen fluoride from electrolyte oxidation decomposition,but SA behaves best.Typically,MA shows adverse effects on the interface stability of Li anode and NCM811 cathode,which originates from its high acidity.Though the acidity of MA can be mitigated by substituting a methyl for one H atom at its C=C bond,the substituent CA cannot compete with SA in cyclic stability improvement of the cell,because the SEI resulting from CA is not as robust as that from SA,which is related to the binding energy of the SEI components.This understanding reveals the importance of the electrolyte acidity on the Ni-rich cathode and the robustness of the SEI on Li anode,which is helpful for rationally designing new electrolyte additives to further improve the cyclic stability of high-energydensity Ni-rich/Li batteries.

Manipulating vector solitons with super-sech pulse shapes

Theoretical simulations about manipulating vector solitons with super-sech pulse shapes are conducted based on an optical fiber system.By changing the temporal pulses’parameters when the orthogonally polarized pulses have the same or different input central wavelengths,the output modes in orthogonal directions will demonstrate different properties.When the input orthogonal modes have the same central wavelength,the“2+2”pseudo-high-order vector soliton can be generated when the time delay is changed.While under the condition of different central wavelengths,orthogonal pulses with multiple peaks accompanied with two wavelengths can be achieved through varying the projection angle,time delay or phase difference.Our simulations are helpful to the study of optical soliton dynamics in optical fiber systems.

Polarization manipulation of bright-dark vector bisolitons

We simulate the polarization manipulation of bright-dark vector bisolitons at 1-µm wavelength regime.Through changing the pulse parameters,different kinds of pulse shapes and optical spectra are generated in output orthogonal polarization directions.When the input vector bisoliton is polarization-locked with 1064 nm central wavelength,“1+1”fundamental dark-dark and“2+1”pseudo-high-order bright-dark group-velocity-locked vector solitons can be achieved through changing the projection angle.When the input vector bisoliton is group-velocity-locked with 1063 nm and 1065 nm central wavelengths,“2+1”and“2+2”pseudo-high-order bright-dark group-velocity-locked vector solitons,bright-dark group-velocity-locked vector solitons with chirp-like temporal oscillations are generated.Our simulation results can provide beneficial conduct for polarization manipulation of vector multi-solitons,and have promising applications in quantum information register,optical communications,nanophotonics,and all-optical switching.

Penpulimab,an anti-PD-1 antibody,for heavily pretreated metastatic nasopharyngeal carcinoma:a single-arm phase II study

Penpulimab is an anti-programmed cell death-1(PD-1)IgG1 antibody with no Fc gamma receptor(FcγR)binding activity,and thus theoretically reduced immune-related adverse events(irAEs)while maintaining efficacy.This single-arm,phase II trial conducted across 20 tertiary care centers in China enrolled adult patients with metastatic nasopharyngeal carcinoma(NPC)who had failed two or more lines of previous systemic chemotherapy.Patients received 200-mg penpulimab intravenously every 2 weeks(4 weeks per cycle)until disease progression or intolerable toxicities.The primary endpoint was objective response rate(ORR)per RECIST(version 1.1),as assessed by an independent radiological review committee.The secondary endpoints included progression-free survival(PFS)and overall survival(OS).One hundred thirty patients were enrolled and 125 were efficacy evaluable.At the data cutoff date(September 28,2022),1 patient achieved complete response and 34 patients attained partial response.The ORR was 28.0%(95%CI 20.3–36.7%).The response was durable,with 66.8%still in response at 9 months.Thirty-three patients(26.4%)were still on treatment.The median PFS and OS were 3.6 months(95%CI=1.9–7.3 months)and 22.8 months(95%CI=17.1 months to not reached),respectively.Ten(7.6%)patients experienced grade 3 or higher irAEs.Penpulimab has promising anti-tumor activities and acceptable toxicities in heavily pretreated metastatic NPC patients,supporting further clinical development as third-line treatment of metastatic NPC.

Highly stabilized and lowly polarized Li anodes using a hybrid surface film with inner Li–Zn nucleation sites and outer LiF-rich protection texture

Lithium(Li)metal is the most promising anode for improving the energy density of currently commercialized Li-ion batteries.However,its practical application is limited due to its high reactivity to electrolytes,which induces severe electrolyte decomposition and Li-dendrite growth.Interphases are usually constructed on Li anode to address the above issue.Meanwhile,it is a big challenge to balance the stability and plating/stripping overpotential of Li anode.In this work,we report a novel strategy for constructing a highly stable and lowly polarized surface film on Li anode.A chemically and structurally unique film is formed by simply dropping a zinc trifluoromethanesulfonate[Zn(OTF)_(2)]and fluoroethylene carbonate(FEC)-containing solution onto Li anode.This unique film consists of inner nucleation sites and outer protection textures,mainly containing Li–Zn alloy and LiF/polymer,respectively.The former results from the preferential reduction of Zn(OTF)_(2),providing nucleation sites with low polarization for Li plating/stripping.In contrast,the latter arises from the subsequent reduction of FEC,providing protection for the underneath Li–Zn alloy and Li metal and ensuring the stability of Li anode.The Li anode with such a unique surface film exhibits excellent cycling stability and low plating/stripping overpotentials,which have been demonstrated using Li//Li symmetric and Li//LiFePO_(4)full cells.

Multiplexed imaging of tumor immune microenvironmental markers in locally advanced or metastatic non-small-cell lung cancer characterizes the features of response to PD-1 blockade plus chemotherapy

Background:Although programmed cell death 1(PD-1)blockade plus chemotherapy can significantly prolong the progression-free survival(PFS)and overall survival(OS)in first-line settings in patients with driver-negative advanced non-small-cell lung cancer(NSCLC),the predictive biomarkers remain undetermined.Here,we investigated the predictive value of tumor immune microenvironmental marker expression to characterize the response features to PD-1 blockade plus chemotherapy.Methods:Tumor tissue samples at baseline were prospectively collected from 144 locally advanced or metastatic NSCLC patients without driver gene alterations who received camrelizumab plus chemotherapy or chemotherapy alone.Tumor immune microenvironmental markers,including PD-1 ligand(PDL1),CD8,CD68,CD4 and forkhead box P3,were assessed using multiplex immunofluorescence(mIF)assays.Kaplan-Meier curveswere used to determine treatment outcome differences according to their expression status.Mutational profiles were compared between tumors with distinct expression levels of these markers and their combinations.Results:Responders had significantly higher CD8/PD-L1(P=0.015)or CD68/PD-L1 co-expression levels(P=0.021)than non-responders in the camrelizumab plus chemotherapy group,while no difference was observed in the chemotherapy group.Patients with high CD8/PD-L1 or CD68/PD-L1 co-expression level was associated with significantly longer PFS(P=0.002,P=0.024;respectively)and OS(P=0.006,P=0.026;respectively)than those with low co-expression in camrelizumab plus chemotherapy group.When comparing survival in the camrelizumab plus chemotherapy with chemotherapy by CD8/PD-L1 co-expression stratification,significantly better PFS(P=0.003)and OS(P=0.032)were observed in high co-expression subgroups.The predictive value of CD8/PD-L1 and CD68/PD-L1 co-expression remained statistically significant for PFS and OS when adjusting clinicopathological features.Although the prevalence of TP53 or KRAS mutations was similar between patients with and without CD8/PD-L1 or CD68/PD-L1 co-expression,the positive groups had a significantly higher proportion of TP53/KRAS co-mutations than the negative groups(both 13.0%vs.0.0%,P=0.023).Notably,enriched PI3K(P=0.012)and cell cycle pathway(P=0.021)were found in the CD8/PD-L1 co-expression group.Conclusion:Tumor immune microenvironmental marker expression,especially CD8/PD-L1 or CD68/PD-L1 co-expression,was associated with the efficacy of PD-1 blockade plus chemotherapy as first-line treatment in patients with advanced NSCLC.

Value and governance of high-speed railway

This paper considers multiple perspectives to explore the concept of high-speed railway(HSR),rationally abstract its value formation mechanism, and quantitatively measure its actual performance. This paper analyzes the governance potential of major countries in the high-speed railway value chain and studies the feasible ways and development strategies to enhance the highspeed railway governance in China. Findings of this paper are as follows. First, the government, as the early manager of high-speed railway governance, has given way to Siemens and other integrated enterprises. Second, the highspeed railway standard output has become the core competitiveness that embodies high-speed railway. Third,the global high-speed railway market presents a hierarchical high-speed railway governance model and changes to a modular approach to governance.

Non-Oxidative Methane Conversion Using Lead- and Iron-Modified Albite Catalysts in Fixed-Bed Reactor

Raw and modified albite catalysts, including Pb/Atbite and Fe/Albite catalysts, have been investigated for methane conversion to C2 hydrocarbons under non-oxidative conditions. Introduction of Pb to albite improved the activity and selectivity to non-coke products. Based on characterization, it was found that Pb entered into the alkali and alkaline-earth metal sites of albite, while partial Fedoped in the tetrahedron sites and the other loaded on the surface of albite. At the reaction temperature of 1073 K, methane gas hourly space velocity （GHSV） of 2 L.gcat-1·h-1, catalyst dosage of 0.25 g （300 mesh）, the methane conversion catalyzed by raw albite in the fixed-bed micro reactor exhibited a methane conversion of 3.32%. Notably, introducing a Pb content of 3.4 wt% into albite greatly enhanced the conversion of methane up to 8.19%, and the selectivity of C2 hydrocarbons reached 99% without any coke under the same reaction conditions. While Fe-doping could weakly heighten the methane conversion to 3.97%, and coke was formed. Thus, a comparison of Pb/Albite and Fe/Albite catalysts demonstrates that the catalytic activity of albite is mainly decided by alkali and alkaline-earth metal sites, and lead-modification can effectively improve the catalytic activity of albite.

内消旋二苯甲酰酒石酸主导苝酰亚胺聚集体超分子手性的反Z-型相关

CD-ee关系曲线常用以描述聚集体的超分子手性特征,其中线型和S(Z)-型相关已有诸多报道,但反S(Z)-型相关却鲜见报道.我们提出通过引入手性诱导剂的内消旋体,构建呈反Z-型相关的超分子聚集体.在手性二苯甲酰酒石酸对映体存在下,修饰以胍基的苝酰亚胺(PBI)分子因为胍基-羧酸根离子间的盐桥氢键作用,聚集形成超分子聚集体, CD信号与二苯甲酰酒石酸对映异构体的对映体过量值(ee)间呈Z-型相关,表现为手性放大特征;于对映体中引入内消旋二苯甲酰酒石酸,摩尔分数达到0.4或超过后观察到罕见的反Z-型相关."将军与士兵"法则实验亦呈现凹型相关曲线.吸收和CD光谱表明,对映异构体与内消旋体分别诱导的聚集体的结构和稳定性相近,后混合体系中聚集体之间无分子交换作用;但荧光光谱实验指示内消旋体更利于PBI染料分子的聚集,与对映体共存时主导聚集体的形成,导致超分子手性的反Z-型相关.研究结果为构筑反S(Z)-型相关的超分子聚集体提供了路径,有助于全面理解超分子手性.

Unified construction of two n-order circuit networks with diodes

In this paper,two different n-order topological circuit networks are connected by diodes to establish a unified network model,which is a previously unexplored problem.The network model includes not only five resistive elements but also diode devices,so the network contains many different network types.This problem can be solved through three main steps:First,the network is simplified into two different equivalent circuit models.Second,the nonlinear difference equation model is established by applying Kirchhoff’s law.Finally,the two equations with similar structures are processed uniformly,and the general solutions of the nonlinear difference equations are obtained by using the transformation technique.As an example,several interesting specific results are deduced.Our study on the network model has significant value,as it can be applied to relevant interdisciplinary research.