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Functionalized Hierarchical ZSM-5 Zeolites for the Viscosity Reduction of Heavy Oil at Low Temperature

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Chemical Research in Chinese Universities 2022年第4期38卷 1083-1088页

作者： XIAO peiwen LI Hui WANG Pingmei LIU Bolun JING Wendan HE Lipeng WANG Runwei HAN xue ZHANG Zongtao QIU Shilun LUO Jianhui Research Institute of Petroleum Exploration&Development PetroChinaBeijing100083P.R.China Key Laboratory of Nano Chemistry(KLNC) CNPCBeijing100083P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun130012P.R.China

Herein,we propose a novel approach to reduce the viscosity of heavy oil by functional hierarchical CTMS-ZSM-5-PTMS ***-ZSM-5-PTMS zeolites synthesized by asymmetric modification and selective alkali etching can reduce the viscosity of heavy oil through adsorbing *** method can reduce the viscosity of heavy oil from hundreds of thousands mPa·s to about ten thousand mPa·*** work provides an economical and environmentally friendly candidate for heavy oil viscosity reduction under low-temperature conditions.

关键词： Heavy oil Viscosity Hierarchical ZSM-5 zeolite

Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming Li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei Li xue-Yuan Liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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人工智能与政治安全形态演变:一项系统研究的尝试

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国际安全研究 2025年第1期43卷 54-72,156,157页

作者：封帅薛世锟上海国际问题研究院网络空间国际治理研究中心上海国际问题研究院上海200233

在人工智能时代,政治安全的内涵正在被不断深化和持续拓展,各国面临的政治安全风险也愈发复杂。根据系统科学理论,政治安全可以构建为一种政治安全系统,包含正反要素、四大结构面与动态稳定的功能。人工智能在经历从游离到输入的时序过... 详细信息

在人工智能时代,政治安全的内涵正在被不断深化和持续拓展,各国面临的政治安全风险也愈发复杂。根据系统科学理论,政治安全可以构建为一种政治安全系统,包含正反要素、四大结构面与动态稳定的功能。人工智能在经历从游离到输入的时序过程后,作为一种新的要素与政治安全系统发生互动。人工智能与政治安全的互动遵循“技术—应用—风险—系统”的逻辑过程,并实现对系统内其他要素的影响。这种影响全面且深刻,使得人工智能开始大面积嵌入政治安全系统,重构了政治安全结构。政治安全正在面临人工智能所带来的更复杂的风险形态,包括权力安全、制度安全与价值安全在内的政治安全内部生态都将发生深刻变化,推动整个政治安全形态经历深刻的变革。

关键词：人工智能政治安全国家安全系统科学

Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： Yi Jing Xin-Ran Liu Xing-Hua Wang Hui Han Sha-Sha Liang Xi-Meng Chen Dong-Hui Wei Lai-Sheng Wang xue-Nian Chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation

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食品科学 2025年第1期46卷 131-141页

作者： SUN Yupeng CHEN Ying SHANG Qingwen GUO Yanyin ZHANG Yuxiao WANG Yunqiao xue Qingyue College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049China Zichuan District Agricultural and Rural Affairs Service Center Zibo 255049China

To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before *** appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of *** results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli ***,during the growth stage,total sugar accumulation was higher in the 5-ARG *** addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest *** conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of ***,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.

关键词： arginine broccoli preharvest spraying nutrient accumulation storage quality postharvest senescence

基于强稳定收敛的偏正态联合位置与尺度模型的参数估计算法

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应用数学 2025年第1期38卷 201-210页

作者：薛潇吴刘仓昆明理工大学理学院云南昆明650500 昆明理工大学应用统计学研究中心云南昆明650500

传统的迭代算法(例如牛顿算法,EM算法等)在实际应用中,往往存在初始值较为敏感的问题.为解决这一问题,一种强稳定的收敛算法――Upper-crossing/Solution算法(以下称US算法)被提出,这种算法虽然在求解一元非线性函数时具有强稳定性,但... 详细信息

传统的迭代算法(例如牛顿算法,EM算法等)在实际应用中,往往存在初始值较为敏感的问题.为解决这一问题,一种强稳定的收敛算法――Upper-crossing/Solution算法(以下称US算法)被提出,这种算法虽然在求解一元非线性函数时具有强稳定性,但是不能推广到多元的情形.那么针对多元情形,本文将结合偏正态分布的随机表示,对偏正态联合位置与尺度模型的似然函数进行分层,并且利用MM算法得到一元的情形,再使用US算法构造强稳定的收敛算法.最后通过随机模拟分析和实例分析研究表明了US算法较牛顿迭代法大大降低了算法对初值的敏感度以及显著地提高了收敛的稳定性.

关键词：偏正态联合位置与尺度模型牛顿迭代法 US算法强稳定收敛

3D printing of cell-delivery scaffolds for tissue regeneration Jianmin xue and others

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Regenerative Biomaterials 2023年第1期10卷 839-852页

作者： Jianmin xue Chen Qin Chengtie Wu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Tissue engineering strategy that combine biomaterials with living cells has shown special advantages in tissue regeneration and promoted the development of regenerative *** particular,the rising of 3D printing technology further enriched the structural design and composition of tissue engineering scaffolds,which also provided convenience for cell loading and cell delivery of living *** this review,two types of cell-delivery scaffolds for tissue regeneration,including 3D printed scaffolds with subsequent cell-seeding and 3D cells bioprinted scaffolds,are mainly *** devote a major part to present and discuss the recent advances of two 3D printed cell-delivery scaffolds in regeneration of various tissues,involving bone,cartilage,skin tissues *** two types of 3D printed cell-delivery scaffolds have some shortcomings,they do have generally facilitated the exploration of tissue engineering scaffolds in multiple tissue *** is expected that 3D printed cell-delivery scaffolds will be further explored in function mechanism of seeding cells in vivo,precise mimicking of complex tissues and even organ reconstruction under the cooperation of multiple fields in future.

关键词： cell-delivery 3D printing tissue regeneration

Research on the Construction of Intellectual Property System and Optimization of Business Environment in China

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科技与法律（中英文） 2025年第1期 125-137页

作者： Zhang xue Lyu Guofu Institute of Intellectual Property Guizhou University of CommerceGuiyang 550014China

With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business *** article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and *** study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously ***,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international *** issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business ***,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite *** aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.

关键词： intellectual property business environment system construction economic development

Role of nutrition in diabetes mellitus and infections

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World Journal of Clinical Cases 2025年第3期13卷 1-8页

作者： xue-Lu Yu Li-Yun Zhou Xiao Huang Xin-Yue Li Ming-Ke Wang Ji-Shun Yang Naval Medical Center of PLA Naval Medical UniversityShanghai 200052China

In this editorial,we have commented on the article that has been published in the recent issue of World Journal of Clinical *** authors have described a case of unilateral thyroid cyst and have opined that the acute onset of infection may be linked to diabetes mellitus(DM).We have focused on the role of nutrition in the association between DM and *** with DM are at a high risk of infection,which could also be attributed to nutrition-related *** interventions for patients with diabetes are mainly based on a low-calorie diet,which can be achieved by adhering to a low-carbohydrate ***,dietary fiber supplementation is recommended to maintain the diversity of the gut ***,high-quality protein can prevent the increased risk of infection due to *** of vitamins C,vitamins A,vitamins D,and folic acid improves blood sugar control and facilitates immune *** deficiencies augment the risk of infection,but the relationship with diabetes is mostly U-shaped and a good intake should be maintained.

关键词： Diabetes mellitus Infection Macronutrients Vitamins Minerals