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Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun Chen Ze He Hong-Hao Ma Lu-Qing wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

pH-sensitive KHA/CMC-Fe^(3+)@CS hydrogel loading and the drug release properties of riboflavin

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Particuology 2024年第3期86卷 13-23页

作者： Jie Song Xi Li Yuhua Niu Lijun Chen Zhiqiang Wei Yidan Li Youqian wang Shaanxi University of Science&Technology Xi'an710021China

To improve drug utilization,reduce the drug administration frequency,increase the release time,and reduce the drug side effects in the human body,we prepared(KHA/CMC-Fe^(3+))@CS hydrogel spheres using green and natural potassium humate(KHA),carboxymethyl cellulose(CMC),and chitosan(CS)as raw materials and Fe3+as a crosslinking agent,and loaded them with riboflavin for drug sustainedrelease study using the drop ball *** tests with FTIR,SEM,TG,and X-ray diffractometer showed that the coordination among KHA,CMC,and Fe^(3+)formed a three-dimensional network structure,where cs was encapsulated on the surface of the hydrogel spheres via noncovalent bonding,resulting in good thermal *** stability,drug loading,swelling,and in vitro release of the(KHA/CMC-Fe^(3+))@CS hydrogel spheres were *** results showed that the hydrogel spheres were significantly pH-sensitive,with 11.16 g/g higher swelling in an alkaline environment(pH=7.4)than that in an acidic environment(pH=1.2).The swelling and drug release process of the hydrogel spheres were analyzed using mathematical models,concluding that the hydrogel swelling follows Schott second-order swelling kinetics,and the drug release mechanism was Fickian delivery mode.

关键词： Potassium humate Hydrogel spheres pH-sensitive Drugsustained-release Drug release model

Development of multi-functional anchorage support dynamic-static coupling performance test system and its application

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International Journal of Mining Science and Technology 2024年第3期34卷 339-349页

作者： Qi wang Shuo Xu Bei Jiang Chong Zhang Zhe Sun Jingxuan Liu Cailin Jiao State Key Laboratory for Tunnel Engineering China University of Mining&Technology-BeijingBeijing 100083China Research Center of Geotechnical and Structural Engineering Shandong UniversityJinan 250061China

In underground engineering with complex conditions,the bolt(cable)anchorage support system is in an environment where static and dynamic stresses coexist,under the action of geological conditions such as high stresses and strong disturbances and construction conditions such as the application of high *** is essential to study the support components performance under dynamic-static coupling *** on this,a multi-functional anchorage support dynamic-static coupling performance test system(MAC system)is developed,which can achieve 7 types of testing functions,including single component performance,anchored net performance,anchored rock performance and so *** bolt and cable mechanical tests are conducted by MAC system under different prestress *** results showed that compared to the non-prestress condition,the impact resistance performance of prestressed bolts(cables)is significantly *** the prestress range of 50–160 k N,the maximum reduction rate of impact energy resisted by different types of bolts is 53.9%–61.5%compared to non-prestress *** the prestress range of 150–300 k N,the impact energy resisted by high-strength cable is reduced by76.8%–84.6%compared to non-prestress *** MAC system achieves dynamic-static coupling performance test,which provide an effective means for the design of anchorage support system.

关键词： Anchorage support system Development of test system Dynamic-static coupling test Combined stress

Monitoring Surface Deformation Using Distributed Scatterers InSAR

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Journal of Geodesy and Geoinformation Science 2024年第1期7卷 42-58页

作者： LI Haocheng DONG Jie wang Yi’an LIAO Mingsheng State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079China

In the past two decades,extensive and in-depth research has been conducted on Time Series InSAR technology with the advancement of high-performance SAR satellites and the accumulation of big SAR *** introduction of distributed scatterers in Distributed Scatterers InSAR(DS-InSAR)has significantly expanded the application scenarios of InSAR geodetic measurement by increasing the number of measurement *** study traces the history of DS-InSAR,presents the definition and characteristics of distributed scatterers,and focuses on exploring the relationships and distinctions among proposed algorithms in two crucial steps:statistically homogeneous pixel selection and phase ***,the latest research progress in this field is tracked and the possible development direction in the future is *** simulation experiments and two real InSAR case studies,the proposed algorithms are compared and verified,and the advantages of DS-InSAR in deformation measurement practice are *** work not only offers insights into current trends and focal points for theoretical research on DS-InSAR but also provides practical cases and guidance for applied research.

关键词： InSAR permanent scatterers distributed scatterers statistically homogeneous pixel selection phase optimization

STAT家族与乳腺癌的关联特点及中药的干预作用

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中国实验方剂学杂志 2024年第7期30卷 225-233页

作者：郭琳王笑冉刘思哲张媛鑫田硕苗明三河南中医药大学郑州450046

随着社会节奏增快及生活方式的改变,乳腺癌的发病率和死亡率持续上升。目前靶向疗法在乳腺癌的治疗中前景良好,已发现多种蛋白靶点在乳腺癌的发生发展中扮演重要角色,其中信号转导和转录激活蛋白(STAT)是一组信号转导和转录激活蛋白,是... 详细信息

随着社会节奏增快及生活方式的改变,乳腺癌的发病率和死亡率持续上升。目前靶向疗法在乳腺癌的治疗中前景良好,已发现多种蛋白靶点在乳腺癌的发生发展中扮演重要角色,其中信号转导和转录激活蛋白(STAT)是一组信号转导和转录激活蛋白,是传导细胞转录信息的重要靶点,该靶点可通过对下游细胞增殖、凋亡、细胞迁移、侵袭及血管生成因子等进行调节,进而影响乳腺癌的进展。STAT家族与肿瘤炎症反应密切相关,在肿瘤的发生发展及诊断、预后中发挥标志性作用。“炎-癌”转化指非可控性炎症导致的炎性微环境促进正常细胞癌变的过程,中医理论认为“癌毒”中的“热毒”与肿瘤发展密切的炎症相对应,因而炎症是导致肿瘤发生的重要因素。作为与炎症反应相关的主要环节,STAT家族对多种肿瘤的发生发展及治疗有一定的作用且前景良好,但其对乳腺癌的相关研究虽有但并未深入。中医药在乳腺癌的防治中已有较好疗效,当前有研究表明,中药有效成分、复方对乳腺癌相关的STAT蛋白有一定的干预作用,但尚未有系统综述。为更好梳理总结中药基于STAT家族干预乳腺癌的作用研究,该文对近年来作用于STAT家族的中药研究进行综述,旨在为乳腺癌的临床应用提供新的思路,也为基于STAT蛋白的药物研发提供思考。

关键词：信号转导和转录激活蛋白乳腺癌中药炎-癌转化 Janus激酶/信号转导和转录激活蛋白(JAK/STAT)通路

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NbB_(2)Modified Al-Cu Alloys Fabricated by Freeze-Ablation Casting under High Cooling Rate Solidification

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 921-938页

作者： Xiang Kong Yu wang Hong Xu Haotian Fan Yuewu Zheng Beibei Xie School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

At present,improving the properties of aluminum alloys is generally achieved by increasing the cooling rate of the melt and adding micro-nano *** the cooling rate of the melt to improve the refining effect of grain refiner is still a difficult problem in the aluminum alloy casting *** innovative and environmentally friendly casting process,known as freeze ablation,was introduced during the preparation of an Al–NbB_(2) intermediate *** process significantly enhanced the cooling rate of the *** results indicated that the Al–NbB_(2) intermediate alloy produced under high cooling rates had a noticeable refining effect on Al–Cu alloys,with smaller NbB2 particles demonstrating superior refining *** average grain size of the refined Al–Cu alloy decreased from 154 to 69μm,the tensile strength increased by 12%,the fluidity increased by 18.4%,and the hot tearing index decreased from 144 to *** matching degree between NbB_(2) andα-Al was calculated using high-resolution transmission electron microscopy and the edge-to-edge *** was found that the atomic interplanar spacing and the interatomic spacing mismatch between NbB_(2)’splane and Al were both less than 10%,which further proved that NbB2 could serve as an effective nucleation site forα-Al grains to achieve grain refinement.

关键词： Grain refinement Freeze ablation Particle size control Mechanical properties Process properties

Application of multi-algorithm ensemble methods in high-dimensional and small-sample data of geotechnical engineering:A case study of swelling pressure of expansive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1896-1917页

作者： Chao Li Lei wang Jie Li Yang Chen School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China Discipline of Civil and Infrastructure Engineering RMIT UniversityMelbourne3001Australia School of Naval Architecture and Civil Engineering Shanghai Jiao Tong UniversityShanghai200240China

Geotechnical engineering data are usually small-sample and high-dimensional,which brings a lot of challenges in predictive *** paper uses a typical high-dimensional and small-sample swell pressure(P_(s))dataset to explore the possibility of using multi-algorithm hybrid ensemble and dimensionality reduction methods to mitigate the uncertainty of soil parameter *** on six machine learning(ML)algorithms,the base learner pool is constructed,and four ensemble methods,Stacking(SG),Blending(BG),Voting regression(VR),and Feature weight linear stacking(FWL),are used for the multi-algorithm ***,the importance of permutation is used for feature dimensionality reduction to mitigate the impact of weakly correlated variables on predictive *** results show that the proposed methods are superior to traditional prediction models and base ML models,where FWL is more suitable for modeling with small-sample datasets,and dimensionality reduction can simplify the data structure and reduce the adverse impact of the small-sample effect,which points the way to feature selection for predictive *** on the ensemble methods,the feature importance of the five primary factors affecting P_(s) is the maximum dry density(31.145%),clay fraction(15.876%),swell percent(15.289%),plasticity index(14%),and optimum moisture content(13.69%),the influence of input parameters on P_(s) is also investigated,in line with the findings of the existing literature.

关键词： Expansive soils Swelling pressure Machine learning(ML) Multi-algorithm ensemble Sensitivity analysis

Design method of extractant for liquid-liquid extraction based on elements and chemical bonds

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Chinese Journal of Chemical Engineering 2024年第4期68卷 193-202页

作者： Yuwen Wei Chunling Zhang Yue Zhang Lili wang Li Xia Xiaoyan Sun Shuguang Xiang Institute of Process System Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China Yantai Guobang Chemical Machinery Technology Co. Ltd.Yantai 264002China

In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and effective separation method, and selecting an extraction agent is the key to extraction technology research. In this paper, a design method of extractants based on elements and chemical bonds was proposed. A knowledge-based molecular design method was adopted to pre-select elements and chemical bond groups. The molecules were automatically synthesized according to specific combination rules to avoid the problem of “combination explosion” of molecules. The target properties of the extractant were set, and the extractant meeting the requirements was selected by predicting the correlation physical properties of the generated molecules. Based on the separation performance of the extractant in liquid-liquid extraction and the relative importance of each index, the fuzzy comprehensive evaluation membership function was established, the analytic hierarchy process determined the mass ratio of each index, and the consistency test results were passed. The results of case study based on quantum chemical analysis demonstrated that effective determination of extractants for the analysis of benzene-cyclohexane systems. The results unanimously prove that the method has important theoretical significance and application value.

关键词： Molecular design Element and chemical bonds Molecular simulation Thermodynamics Solvent extraction

The response of roots and the rhizosphere environment to integrative cultivation practices in paddy rice

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Journal of Integrative Agriculture 2024年第6期23卷 1879-1896页

作者： Hanzhu Gu Xian wang Minhao Zhang Wenjiang Jing Hao Wu Zhilin Xiao Weiyang Zhang Junfei Gu Lijun Liu Zhiqin wang Jianhua Zhang Jianchang Yang Hao Zhang Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops/Agricultural College Yangzhou UniversityYangzhou 225009China Taizhou Institute of Agricultural Science Jiangsu Academy of Agricultural SciencesTaizhou 225300China State Key Laboratory of Agrobiotechnology School of Life SciencesThe Chinese University of Hong KongShatinHong Kong 999077China Department of Biology Faculty of ScienceHong Kong Baptist UniversityKowloonHong Kong 999077China

Integrative cultivation practices(ICPs)are essential for enhancing cereal yield and resource use ***,the effects of ICP on the rhizosphere environment and roots of paddy rice are still poorly *** this study,four rice varieties were produced in the *** variety was treated with six different cultivation techniques,including zero nitrogen application(0 N),local farmers’practice(LFP),nitrogen reduction(NR),and three progressive ICP techniques comprised of enhanced fertilizer N practice and increased plant density(ICP1),a treatment similar to ICP1 but with alternate wetting and moderate drying instead of continuous flooding(ICP2),and the same practices as ICP2 with the application of organic fertilizer(ICP3).The ICPs had greater grain production and nitrogen use efficiency than the other three *** length,dry weight,root diameter,activity of root oxidation,root bleeding rate,zeatin and zeatin riboside compositions,and total organic acids in root exudates were elevated with the introduction of the successive cultivation *** enhanced nitrate nitrogen,the activities of urease and invertase,and the diversity of microbes(bacteria)in rhizosphere and non-rhizosphere soil,while reducing the ammonium nitrogen *** nutrient contents(ammonium nitrogen,total nitrogen,total potassium,total phosphorus,nitrate,and available phosphorus)and urease activity in rhizosphere soil were reduced in all treatments in comparison with the non-rhizosphere soil,but the invertase activity and bacterial diversity were *** main root morphology and physiology,and the ammonium nitrogen contents in rhizosphere soil at the primary stages were closely correlated with grain yield and internal nitrogen use *** findings suggest that the coordinated enhancement of the root system and the environment of the rhizosphere under integrative cultivation approaches may lead to higher rice production.

关键词： rice(Oryza sativa L.) nitrogen use efficiency grain yield integrative cultivation practices roots