Effect of cyclic wetting-drying on tensile mechanical behavior and microstructure of clay-bearing sandstone

The understanding of the weakening mechanism of tensile strength of rock subjected to cyclic wetting-drying is critical for rock engineering.Tensile strength tests were conducted on a total of 35 sandstone specimens with different wetting-drying cycles.The crack propagation process and acoustic emission characteristics of the tested samples were obtained through a high-speed camera and acoustic emission system.The results indicate that the tensile strength is observably reduced after cyclic wetting-drying,and the extent of the reduction is not only related to the number of wettingdrying cycle,but also closely related to the clay mineral content of the sample.In addition,as the cycles of wetting-drying increase,the effect of each single cycle on tensile strength get reduced until it becomes constant.Moreover,the crack initiation and penetration time is prolonged as the number of wetting-drying cycle increases,which indicates that cyclic wetting-drying weakens the rock stiffness and enhances the ductility of sandstone.Meanwhile,the acoustic emission characteristics of the tested samples further confirmed the ductile behaviour of the sandstone samples with increasing wetting-drying cycle.Furthermore,through the analysis of the microstructure and mineral composition of the samples with different wetting-drying cycles,it is concluded that the main weakening mechanisms of sandstones containing clay minerals are frictional reduction,chemical and corrosive deterioration.

The tuning of pore structures and acidity for Zn/Al layered double hydroxides:The application on selective hydrodesulfurization for FCC gasoline

Co–Mo catalysts applied on the hydrodesulfurization（HDS） for FCC gasoline were prepared with Zn–Al layered double hydroxides（LDHs） to improve their performances,and the effects of pore structures and acidity on HDS performances were studied in detail. A series of Zn–Al/LDHs samples with different pore structures and acidities are synthesized on the bases of co-precipitation of OH-,CO2-,Al3＋,and Zn2＋. The neutralization p H is a main factor to affect the pore structures and acidity of Zn–Al/LDHs,and a series of Zn–Al/LDHs with different pore structures and acidities are obtained. Based on the representative samples with different specific surface areas（SBET） and acidities,three Co Mo/LDHs catalysts were prepared,and their HDS performances were compared with traditional Co Mo/Al2O3 catalysts. The results indicated that catalysts prepared with high SBETpossessed high HDS activity,and Br？nsted acid sites could reduce the thiol content in the product to some extent. All the three catalysts prepared with LDHs displayed little lower HDS activity but higher selectivity than Co Mo/Al2O3,and could restrain the reactions of re-combination between olefin and H2 S which could be due to the existence of Br？nsted acid sites.

Reactive adsorption desulfurization coupling aromatization on Ni/ZnO-Zn_6Al_2O_9 prepared by Zn_xAl_y(OH)_2(CO_3)_z·x H_2O precursor for FCC gasoline

Aiming to improve the reactive adsorption desulfurization（RADS） performances of Ni/Zn O adsorbents,ZnxAly（OH）2（CO3）z·x H2 O precursor is synthesized by coprecipitation of Zn2＋,AlO-2,and CO2-3; the Zn OZn6Al2O9 composite oxides are obtained by the calcination of ZnxAly（OH）2（CO3）z·x H2 O precursor,and the Ni/Zn O-Zn6Al2O9（6.0 wt% Ni O） adsorbents are prepared by wetness impregnation method. The phase,acid strength,acid type and quantity,morphology,and thermal properties were characterized by X-ray diffraction,temperature-programmed desorption of ammonia,pyridine-adsorbed infrared spectrum,high-resolution transmission electron microscopy,and Thermo Gravimetry-Derivative Thermo Gravimetry（TG-DTG）,respectively. The breakthrough sulfur capacities of six adsorbents are between 34.2 and 47.9 mg/gcat. The kinetic studies indicated that the active energy of RADS（49.4 k J/mol） could reach nano-sized Zn O,the particle size of is about 12.0 nm. All the excellent RADS performances can be due to the high SBET. Also,there are some extents of aromatization reactions that occur,which can be contributed to the B？nsted acid rooted in Zn6Al2O9 composite oxide,and the octane number of products can be preserved well.

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.

Prediction of treatment response to antipsychotic drugs for precision medicine approach to schizophrenia:randomized trials and multiomics analysis

Background:Choosing the appropriate antipsychotic drug(APD)treatment for patients with schizophrenia(SCZ)can be challenging,as the treatment response to APD is highly variable and difficult to predict due to the lack of effective biomarkers.Previous studies have indicated the association between treatment response and genetic and epigenetic factors,but no effective biomarkers have been identified.Hence,further research is imperative to enhance precision medicine in SCZ treatment.Methods:Participants with SCZ were recruited from two randomized trials.The discovery cohort was recruited from the CAPOC trial(n=2307)involved 6 weeks of treatment and equally randomized the participants to the Olanzapine,Risperidone,Quetiapine,Aripiprazole,Ziprasidone,and Haloperidol/Perphenazine(subsequently equally assigned to one or the other)groups.The external validation cohort was recruited from the CAPEC trial(n=1379),which involved 8 weeks of treatment and equally randomized the participants to the Olanzapine,Risperidone,and Aripiprazole groups.Additionally,healthy controls(n=275)from the local community were utilized as a genetic/epigenetic reference.The genetic and epigenetic(DNA methylation)risks of SCZ were assessed using the polygenic risk score(PRS)and polymethylation score,respectively.The study also examined the genetic-epigenetic interactions with treatment response through differential methylation analysis,methylation quantitative trait loci,colocalization,and promoteranchored chromatin interaction.Machine learning was used to develop a prediction model for treatment response,which was evaluated for accuracy and clinical benefit using the area under curve(AUC)for classification,R^(2) for regression,and decision curve analysis.Results:Six risk genes for SCZ(LINC01795,DDHD2,SBNO1,KCNG2,SEMA7A,and RUFY1)involved in cortical morphology were identified as having a genetic-epigenetic interaction associated with treatment response.The developed and externally validated prediction model,which incorporated clinical information,PRS,genetic risk score(GRS),and proxy methylation level(proxyDNAm),demonstrated positive benefits for a wide range of patients receiving different APDs,regardless of sex[discovery cohort:AUC=0.874(95%CI 0.867-0.881),R^(2)=0.478;external validation cohort:AUC=0.851(95%CI 0.841-0.861),R^(2)=0.507].Conclusions:This study presents a promising precision medicine approach to evaluate treatment response,which has the potential to aid clinicians in making informed decisions about APD treatment for patients with SCZ.Trial registration Chinese Clinical Trial Registry(https://www.chictr.org.cn/),18 Aug 2009 retrospectively registered:CAPOC-ChiCTR-RNC-09000521(https://www.chictr.org.cn/showproj.aspx?proj=9014),CAPEC-ChiCTRRNC-09000522(https://www.chictr.org.cn/showproj.aspx?proj=9013).

The ZOS7-MYB60 module confers drought-stress tolerance in rice

Shanlan upland rice is an important landrace resource with high drought stress(DS)tolerance.Despite its importance,genes responsible for yield in Shanlan upland rice have yet to be discovered.Our previous study identified a drought-responsive zinc finger protein,ZOS7,as highly expressed in Shanlandao upland rice.However,the function of this gene in controlling drought tolerance remains largely unexplored.In this study,we found that overexpressing ZOS7,a drought-responsive zinc finger protein,in rice increased biomass and yield under drought stress.Co-overexpressing ZOS7 and MYB60,encoding a protein with which ZOS7 interacted,intensified the yield increase.ZOS7 and MYB60 appear to form a module that confers drought tolerance by regulating stomatal density and wax biosynthesis.The ZOS7-MYB60module could be used in molecular breeding for drought tolerance in rice.

Behaviour recognition based on the integration of multigranular motion features in the Internet of Things

With the adoption of cutting-edge communication technologies such as 5G/6G systems and the extensive development of devices,crowdsensing systems in the Internet of Things(IoT)are now conducting complicated video analysis tasks such as behaviour recognition.These applications have dramatically increased the diversity of IoT systems.Specifically,behaviour recognition in videos usually requires a combinatorial analysis of the spatial information about objects and information about their dynamic actions in the temporal dimension.Behaviour recognition may even rely more on the modeling of temporal information containing short-range and long-range motions,in contrast to computer vision tasks involving images that focus on understanding spatial information.However,current solutions fail to jointly and comprehensively analyse short-range motions between adjacent frames and long-range temporal aggregations at large scales in videos.In this paper,we propose a novel behaviour recognition method based on the integration of multigranular(IMG)motion features,which can provide support for deploying video analysis in multimedia IoT crowdsensing systems.In particular,we achieve reliable motion information modeling by integrating a channel attention-based short-term motion feature enhancement module(CSEM)and a cascaded long-term motion feature integration module(CLIM).We evaluate our model on several action recognition benchmarks,such as HMDB51,Something-Something and UCF101.The experimental results demonstrate that our approach outperforms the previous state-of-the-art methods,which confirms its effective-ness and efficiency.

Effects and mechanisms of Helicobacter pylori infection on the occurrence of extra-gastric tumors

Helicobacter pylori(H.pylori)colonizes the human stomach and many studies have discussed the mechanisms of H.pylori infection leading to gastric diseases,including gastric cancer.Additionally,increasing data have shown that the infection of H.pylori may contribute to the development of extra-gastric diseases and tumors.Inflammation,systemic immune responses,microbiome disorders,and hypergastrinemia caused by H.pylori infection are associated with many extra-gastric malignancies.This review highlights recent discoveries;discusses the relationship between H.pylori and various extra-gastric tumors,such as colorectal cancer,lung cancer,cholangiocarcinoma,and gallbladder carcinoma;and explores the mechanisms of extra-gastric carcinogenesis by H.pylori.Overall,these findings refine our understanding of the pathogenic processes of H.pylori,provide guidance for the clinical treatment and management of H.pylori-related extra-gastric tumors,and help improve prognosis.

Tailoring Electrode–Electrolyte Interface Using an Electron-Deficient Borate-Based Additive in MgTFSI_(2)-MgCl_(2)/DME Electrolyte for Rechargeable Magnesium Batteries

Rechargeable magnesium metal batteries need an electrolyte that forms a stable and ionically conductive solid electrolyte interphase(SEI)on the anodes.Here,we used molecular dynamic simulation,density functional theory calculation,and X-ray photoelectron spectroscopy analysis to investigate the solvation structures and SEI compositions in electrolytes consisting of dual-salts,magnesium bis(trifluoromethanesulfonyl)imide(MgTFSI_(2)),and MgCl_(2),with different additives in 1,2-dimethoxyethane(DME)solvent.We found that the formed[Mg_(3)(μ-Cl)_(4)(DME)mTFSI_(2)](m=3,5)inner-shell solvation clusters in MgTFSI_(2)-MgCl_(2)/DME electrolyte could easily decompose and form a MgO-and MgF_(2)-rich SEI.Such electron-rich inorganic species in the SEI,especially MgF_(2),turned out to be detrimental for Mg plating/stripping.To reduce the MgF_(2)and MgO contents in SEI,we introduce an electron-deficient tri(2,2,2-trifluoroethyl)borate(TFEB)additive in the electrolyte.Mg//Mg cells using the MgTFSI_(2)-MgCl_(2)/DME-TFEB electrolyte could cycle stably for over 400 h with a small polarization voltage of~150 mV.Even with the presence of 800 ppm H_(2)O,the electrolyte with TFEB additive could still preserve its good electrochemical performance.The optimized electrolyte also enabled stable cycling and high-rate capability for Mg//Mo6S8 and Mg//CuS full cells,showing great potential for future applications.

新工科背景下化工类专业课程思政建设与探索

从学院层面的改革视角出发,以实证研究的方法,围绕立德树人根本任务,按照“边研究、边实践、边完善”的思路,积极探索“新工科”背景下如何从育人理念、专业教师课程思政意识和能力提升、思政元素挖掘、思政教学设计、思政教学评价和激励机制健全等方面全面开展化工类专业课程思政建设,为培养具有时代担当的全面发展的“新工科”化工类高素质人才提供实现路径。

原位透射电镜研究正交相五氧化二铌纳米片的电化学储钠机制

由于正交相五氧化二铌(T-Nb_(2)O_(5))为ReO_(3)型层状结构,锂、钠离子可以在其(001)平面快速脱嵌,而在[001]方向的传输一般较难。本研究通过原位透射电子显微镜(Transmission Electron Microscope,TEM)方法研究钠在T-Nb_(2)O_(5)纳米片(001)面内及[001]方向的钠离子电化学嵌入行为,发现由于纳米片晶体存在大量的位错和畴界,钠离子可通过这些缺陷穿越(001)面扩散,并进而在深层的(001)面内快速扩散。同时,本研究还发现刚合成的T-Nb_(2)O_(5)纳米片在[001]方向上存在调制结构,存在交替分布的压应变和张应变区域,而钠离子的嵌入可以调节这些应变分布。

石墨烯嵌锂的拉曼成像

锂离子电池由于具有高能量密度,高循环寿命,低自放电率的优势,成为当前使用最为广泛的储能器件。层状材料是极为常用的负极材料,其微观嵌锂行为的研究对提高电池的能量密度和循环寿命有重要意义。本工作发展了一种新的平板微电池结构,可用于研究锂离子在各类二维层状纳米材料中的嵌锂行为。我们用机械剥离的单片少层石墨烯为正极,热蒸镀的锂金属为负极,构成石墨烯电池,用恒电压放电的方法进行嵌锂测试。采用拉曼成像技术收集石墨烯G峰信号的空间分布,实现对锂的嵌入过程的显微观测。发现了锂在石墨烯中沿层间扩散迁移,以及石墨烯断层对锂扩散的阻碍作用。这些结果有助于理解放电时锂在石墨烯电极中扩散过程,并且这项研究开发的平板微电池结构可用于多种材料的电化学过程中的微观过程表征,同时可实现与光学、电学、电子显微学等多种表征手段的兼容,具有较好的应用前景。

基于CART的高校教师亚健康决策模型构建

传统高校教师亚健康评估缺乏时效性、客观性、高效性。利用大数据技术建立了亚健康决策模型,以支持高校教师亚健康状态的评估与预测。首先针对高校教师亚健康影响因素进行多维分析,构建亚健康多维影响概念模型,其次对样本数据特征进行分析及数据预处理,在此基础上,利用CART算法给出亚健康决策模型建模的详细过程。最后,给出基于Spark的并行实现过程及实验验证。高校教师亚健康概念模型客观反映教师亚健康评估因素,决策树模型能够支持高校教师亚健康预测分析,实验验证该模型的有效性、即时性、准确性。

多因素自适应心跳检测算法研究

分布式系统中心跳检测是节点故障检测机制的关键技术之一,心跳频率设定的合理性将影响到故障检测的准确性和完整性。针对大数据环境下,分布式系统产生故障受到网络、节点、作业多方面影响,为了提高心跳频率在多方面因素影响下的合理性设定,提出一种多因素心跳检测综合指标评价模型。在该模型下同时考虑网络负载情况和节点CPU工作状态及节点作业的大小对心跳检测过程的影响。在此基础上,提出了基于多因素评价模型的自适应心跳检测算法。该算法可以随网络环境、节点CPU占用率、作业任务大小自适应地改变心跳频率,综合各因素给出心跳频率设定的最优方案。最后通过实验验证了多因素对心跳频率自适应调整的影响。

Airline Disruption Management:A Review of Models and Solution Methods

The normal operation of aircraft and flights can be affected by various unpredictable factors,such as severe weather,airport closure,and corrective maintenance,leading to disruption of the planned schedule.When a disruption occurs,the airline operation control center performs various operations to reassign resources(e.g.,flights,aircraft,and crews)and redistribute passengers to restore the schedule while minimizing costs.We introduce different sources of disruption and corresponding operations.Then,basic models and recently proposed extensions for aircraft recovery,crew recovery,and integrated recovery are reviewed,with the aim of providing models and methods for different disruption scenarios in the practical implementation of airlines.In addition,we provide suggestions for future research directions in these topics.

纳米TiO_(2)/Ag复合水性温敏聚氨酯整理剂的应用研究

采用原位负载法制得纳米TiO_(2)/Ag复合水性温敏聚氨酯(TiO_(2)/Ag-WTSPU)乳液,将其用于织物整理,测试了整理织物的表面形貌、力学性能、抗紫外线及抗菌等性能,结果表明:整理后织物的力学性能、抗紫外线性以及抗菌性均增强,且随着纳米TiO_(2)、Ag含量增加,各项性能更优异,当纳米TiO_(2)、Ag含量均为0.4%时,织物的断裂强力和拉伸长度分别为393.2 N、42.2 mm;织物的紫外防护系数为53.7,长波紫外线透过率为4.96%;对大肠杆菌与金黄色葡萄球菌的抑制效果良好;且织物在20~30℃透湿量增加较明显,显示较好温敏特性,织物在40℃时的透湿量达2480 g/(m^(2)·d).

Work roll thermal contour prediction model of nonoriented electrical steel sheets in hot strip mills

The demands for profile and flatness of nonoriented electrical steels are becoming more and more severe. The temperature field and thermal contour of work rolls are the key factors that affect the profile and flatness control in the finishing trains of the hot rolling. A theoretic mathematical model was built by a two-dimensional finite difference to calculate the temperature field and thermal contour at any time within the entire rolling campaign in the hot rolling process. To improve the calculating speed and precision, some special solutions were introduced, including the development of this model, the simplification of boundary conditions, the computation of heat transfer coefficient, and the narrower mesh along the edge of the strip. The effects of rolling pace and work roll shifting on the temperature field and thermal contour of work rolls in the hot rolling process were demonstrated. The calculated results of the prediction model are in good agreement with the measured ones and can be applied to guiding profile and flatness control of nonoriented electrical steel sheets in hot strip mills.

纳米TiO2/聚乙烯醇复合水凝胶膜材料的性能及抗老化应用

为探索纳米TiO2/聚乙烯醇(PVA)复合水凝胶膜对纺织材料的保护作用,以纳米TiO2对PVA水凝胶膜进行改性,改变纳米TiO2含量,考察了这一系列膜的结构与性能。结果表明:纳米TiO2的加入量为5.0%时,其综合性能较佳,此时复合水凝胶膜的拉伸强度为9.41MPa,最大紫外透过率仅为74.94%,透明度达69.82%,选取纳米TiO2含量为5%的复合水凝胶膜,以白棉为例,将合成的复合水凝胶对纺织材料样品进行处理,发现处理后的样品在经紫外光照射一段时间后,其性能变化不大,而未处理的样品在经紫外光照射后,其纤维结构有明显损伤,失重率达6.77%、力峰值损失达18.28%、白度值也明显下降,这表明合成的水凝胶对纺织材料具有保护作用。

人工加速老化对老式胶卷结构与性能的影响

以老式胶卷为例,采用热氧老化、光老化、酸碱水解老化人工加速的方法对其进行老化处理,表征了老化前后各样品的热性能、表面形态和力学性能﹒研究结果表明:人工加速老化方法可以强化老化因素,有效确定各因素对老式胶卷老化程度的影响;光、热、氧气、酸或碱水解等均对老式胶卷的老化有影响,光照作用及碱水解对其结构与性能的影响较大;老化时间的增加会使老式胶卷结构与性能的损伤增大﹒

3GHz边耦合直线加速结构单元腔优化设计

利用CST studio suite程序对边耦合直线加速结构的加速腔及耦合腔进行建模仿真,并进行优化。加速腔结构由11个参数决定,优化过程需平衡多个参数,包括本征模式、高频特性、最大表面电场、有效分路阻抗及渡越时间因子;耦合腔的优化基于维持本征模式3 GHz。结果表明,在26~120 MeV整个加速过程中,加速腔的有效分路阻抗为22.5~59.8 MΩ·m^(-1),加速梯度为11~14.7 MV·m^(-1)。