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Enantioselective reductive conjugate alkenylation ofα,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He yun-lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis,yet their asymmetric variant remains ***,asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–*** manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl *** method facilitates the enantioselective addition of keto alkenyl groups toα,β-enones,resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access *** use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Numerical-Experimental Analysis of the Coal Fracture Formation Mechanism Induced by Liquid CO_(2) Explosion

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Fluid Dynamics & Materials Processing 2023年第12期19卷 3021-3032页

作者： yun lei Shenyang Research Institute China Coal Technology&Engineering Group Corp.Fushun113122China State Key Laboratory of Coal Mine Safety Technology Fushun113122China

The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry.A possible way to solve this problem under deep and complex geological conditions is represented by the technology based on the phase-change induced explosion of liquid carbon *** this work,the mechanism of formation of the coal mass fracture circle resulting from the gas cracking process is theoretically *** simulations show that a blasting crushing zone with a radius of 1.0 m is formed around the blasting *** radius of the sec-ondary expansion zone caused by the exploding gas is 2.0 m,and the extension limit of the explosion fracture is 2.3 *** gas phase change explosion is influenced by the coal roadway driving face,the gas content index and the analytical index of coal *** conducted for comparison also lead to the conclusion that the initial gas emission is increased by 3.7 times from the 100-meter borehole in the original coal mass after coalbed gas explosion anti-reflection.

关键词： Low-permeability gas-rich carbon dioxide anti-reflection gas explosion

一株小菇属天麻萌发菌原生质体的制备、再生和应用

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陕西科技大学学报 2025年第1期43卷 58-66页

作者：李宏敬李锡琴粟忠祥仇全雷雷云霆西南林业大学林学院云南昆明650224 中国科学院昆明植物研究所云南昆明650201 昆明市林草局西山林场云南昆明650199 西藏波密高原藏天麻产业开发有限公司西藏林芝860318

小菇属真菌(Mycena spp.)遗传转化体系是研究其促进天麻种子萌发机制的重要基础,而其原生质体的制备和再生是该体系构建的必要条件.以小菇菌株MY004为实验材料,通过单因素分析和正交试验策略,探究其原生质体制备和再生的影响因素,构建... 详细信息

小菇属真菌(Mycena spp.)遗传转化体系是研究其促进天麻种子萌发机制的重要基础,而其原生质体的制备和再生是该体系构建的必要条件.以小菇菌株MY004为实验材料,通过单因素分析和正交试验策略,探究其原生质体制备和再生的影响因素,构建小菇原生质体制备和再生体系.结果表明,在含10 mM MES和0.7 M甘露醇的酶解缓冲液(pH=6)中,小菇MY004菌丝被10 mg/mL真菌溶壁酶在24℃条件下酶解3 h,其原生质体的释放率较高;经液体再生培养基(pH=5)培养3天,其原生质体再生效率可达2%.利用该体系,高效地完成了含报告基因eGFP转基因小菇的菌株纯化.小菇原生质体制备和再生体系可用于小菇遗传转化体系的快速构建,也将为小菇与天麻互作分子机制的研究提供基础平台.

关键词：小菇原生质体制备原生质体再生转基因菌株纯化

维普期刊数据库博看期刊

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素阶数域上的高效格基数字签名方案

软件学报 2025年第2期36卷 776-804页

作者：董怡帆方博越梁志闯赵运磊复旦大学计算机科学技术学院上海200433 密码科学技术全国重点实验室北京100878

随着量子计算的快速发展,特别是Shor量子算法及其变体的优化进步,当前基于大整数分解和离散对数问题的经典公钥密码体制将面临颠覆性的影响.为了应对量子攻击,学界开始对后量子密码学的研究,其中基于格的后量子密码方案因其在安全、效... 详细信息

随着量子计算的快速发展,特别是Shor量子算法及其变体的优化进步,当前基于大整数分解和离散对数问题的经典公钥密码体制将面临颠覆性的影响.为了应对量子攻击,学界开始对后量子密码学的研究,其中基于格的后量子密码方案因其在安全、效率、带宽等方面的均衡表现和良好的可扩展性而成为后量子密码的主流技术路线.目前,基于格的后量子密码方案大多使用分圆环,尤其是二次幂分圆环作为底层代数结构.但分圆环中具有丰富的子域、自同构、环同态等代数结构,容易遭受针对性攻击.基于具有“高安全性、素数阶、大Galois群和惰性模数”特点的素阶数域,设计出后量子数字签名方案Dilithium-Prime,并给出推荐参数集.然而,素阶数域的一个显著缺点是无法直接使用快速数论变换(NTT)算法进行高效的多项式乘法,导致素阶数域上的密码方案性能较差.为此,设计素阶数域上的NTT算法和小多项式乘法,实现素阶数域上高效的多项式乘法.最后,为方案的关键算法设计常数时间无分支实现方法,给出方案的C语言实现,并与其他方案进行对比.实验结果表明,在同一安全等级下,与分圆环上的数字签名方案CRYSTALS-Dilithium推荐参数相比,Dilithium-Prime方案的公钥尺寸、私钥尺寸、签名尺寸分别降低1.8%、10.2%、1.8%,签名算法效率提高11.9%,密钥生成算法、验证算法所需时间分别为CRYSTALS-Dilithium方案的2.0倍和2.5倍,但不同于CRYSTALS-Dilithium,Dilithium-Prime方案具有抵抗针对分圆环的密码攻击的优越特性;与2023年韩国后量子密码算法竞赛中提出的基于素阶数域的签名方案NCC-Sign推荐参数相比,在相同的安全等级和带宽条件下,Dilithium-Prime方案的密钥生成算法、签名算法、验证算法的速度分别提升至4.2倍、35.3倍、7.2倍,实现兼顾高效性和安全性的素阶数域签名算法.

关键词：后量子密码格密码素阶数域数字签名方案快速数论变换小多项式乘法

Analysis of Crystallization Behavior of Mold Fluxes Containing TiO_2 Using Single Hot Thermocouple Technique

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Journal of Iron and Steel Research International 2016年第4期23卷 322-328页

作者： yun lei Bing XIE Wen-hui MA State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology College of Materials Science and Engineering Chongqing University

The crystallization behavior of mold fluxes containing 0-8 mass% TiO2 was investigated using the single hot therrnocouple technique （SHTT） and X ray diffraction （XRD） to study the possible effects on the coordination of heat transfer control and strand lubrication for casting crack sensitive peritectic steels. Time-temperature-transforma tion （TTT） and continuous-cooling transformation （CCT） curves were plotted using the data obtained from SHTT to characterize the crystallization of the mold fluxes. The results showed that crystallization of the mold fluxes during isothermal and non-isothermal processes was suppressed with TiO2 addition. From the TTT curves, it could be seen that the incubation and growth time of crystallization increased significantly with TiO2 addition. The CCT curves showed that the crystallization temperature initially decreased, and then suddenly increased with increasing the TiO2 content. XRD analysis suggested the presence of cuspidine in the mold fluxes with lower TiO2 content （〈4 mass%） , while both perovskite and cuspidine were detected in the mold fluxes when the TiO2 content was increased to 8 mass%. In addition, the growth mechanisms of the crystals changed during the isothermal crystallization process from interface controlled growth to diffusion-controlled growth with increasing the TiO2 content.

关键词： mold flux single hot thermocouple technique kinetics crystallization TTT curve CCT curve

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素阶数域上的高效紧凑NTRU密钥封装方案

软件学报 2025年第2期36卷 747-775页

作者：梁志闯赵旭阳方博越赵运磊复旦大学计算机科学技术学院上海200433 密码科学技术国家重点实验室北京100036

基于格(特别是NTRU格)设计后量子密钥封装方案是格密码领域的主流方向之一.现有多数格密码方案基于分圆环构造,但分圆环饱含丰富的代数结构导致这些方案容易遭受相关攻击.一个可选的且更安全的代数结构是大Galois群、素数阶、基于素理... 详细信息

基于格(特别是NTRU格)设计后量子密钥封装方案是格密码领域的主流方向之一.现有多数格密码方案基于分圆环构造,但分圆环饱含丰富的代数结构导致这些方案容易遭受相关攻击.一个可选的且更安全的代数结构是大Galois群、素数阶、基于素理想的数域(简称为素阶数域).NTRU-Prime是一个基于素阶数域的备受青睐的NTRU密钥封装方案,且早已经在国际标准OpenSSH中默认应用.旨在设计出比NTRU-Prime性能更优的素阶数域上NTRU密钥封装方案.首先,梳理分圆环的安全隐患,特别是针对2次幂分圆环的系列攻击,同时展示出素阶数域在抵御这些攻击方面的安全优势.接着,基于素阶数域提出NTRU密钥封装方案CNTR-Prime,并给出详细的相关分析和参数集.然后,提出一种伪梅森数不完整NTT,它能有效计算CNTR-Prime中关于素阶数域的多项式乘法.此外,还提出一种改进的伪梅森数约减算法,并将它应用在伪梅森数不完整NTT中.它在软件实现方面比Barrett约减快2.6%,在硬件实现方面比Montgomery约减和Barrett约减快2–6倍.最后,提供CNTR-Prime的C语言实现,并与其他同类方案进行全面对比.结果表明,与SNTRU-Prime相比,CNTR-Prime在安全强度、带宽和实现效率上有优势,其中CNTR-Prime-761的经典和量子安全强度都比SNTRU-Prime-761的高19 bit,密文尺寸降低8.3%,密钥生成算法、密钥封装算法和解封装算法分别快25.3倍、10.8倍和2.0倍.实际上,CNTR-Prime-653的经典和量子安全强度已可与SNTRU-Prime-761相媲美,且CNTR-Prime-653的带宽降低13.8%,密钥生成算法、密钥封装算法和解封装算法分别快33.9倍、12.6倍和2.3倍.所提工作可为后续同类型的格密码方案的设计、分析和优化实现提供重要参考.

关键词：格密码后量子密码数论研究单元(NTRU) 素阶数域密钥封装方案数论变换模约减软件实现

One-pot Three-component Mannich Reaction Catalyzed by 2-Hydroxylpyridine

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Chemical Research in Chinese Universities 2013年第4期29卷 710-713页

作者： JIN Li-li lei yun-tao College of Sciences China Pharmaceutical University Nanjing 210009 P. R. China

An effcient synthetic protocol for the β-amino carbonyl compounds was developed via one-pot three- component Mannich reaction of aromatic aldehydes, aromatic amines and cyclohexanone catalyzed by 2-hydroxylpy- ridine under mild reaction conditions, β-Amino carbonyl compounds were obtained in moderate to good yields and rea- sonable diastereoselectivities. The effects of different solvents, catalyst amounts and the scope of different substrates on the Mannich reactions were investigated. The plausible reaction mechanism was also discussed.

关键词： 2-Hydroxylpyridine Catalyze Mannich reaction fl-Amino carbonyl compound

Practical Constant-Size Ring Signature

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Journal of Computer Science & Technology 2018年第3期33卷 533-541页

作者： Meng-Jun Qin yun-lei Zhao Zhou-Jun Ma Shanghai Key Laboratory of Data Science School of Computer Science Fudan University Shanghai 201203 China State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710126 China State Key Laboratory of Cryptology State Cryptology Administration Beijing 100878 China

Bitcoin has gained its popularity for almost 10 years as a ＂secure and anonymous digital currency＂. However, according to several recent researches, we know that it can only provide pseudonymity rather than real anonymity, and privacy has been one of the main concerns in the system similar to Bitcoin. Ring signature is a good method for those users who need better anonymity in cryptocurrency. It was first proposed by Rivest et al. based upon the discrete logarithm problem （DLP） assumption in 2006, which allows a user to sign a message anonymously on behalf of a group of users even without their coordination. The size of ring signature is one of the dominating parameters, and constant-size ring signature （where signature size is independent of the ring size） is much desirable. Otherwise, when the ring size is large, the resultant ring signature becomes unbearable for power limited devices or leads to heavy burden over the communication network. Though being extensively studied, currently there are only two approaches for constant-size ring signature. Achieving practical constant-size ring signature is a long-standing open problem since its introduction. In this work, we solve this open question. We present a new constant-size ring signature scheme based on bilinear pairing and accumulator, which is provably secure under the random oracle （RO） model. To the best of our knowledge, it stands for the most practical ring signature up to now.

关键词： ring signature constant size bilinear pairing accumulator

Order-Revealing Encryption:File-Injection Attack and Forward Security

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Journal of Computer Science & Technology 2021年第4期36卷 877-895页

作者： Yuan Li Xing-Chen Wang Lin Huang yun-lei Zhao School of Computer Science Fudan UniversityShanghai 201203China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China State Key Laboratory of Cryptology Beijing 100878China

Order-preserving encryption(OPE)and order-revealing encryption(ORE)are among the core ingredients for encrypted databases(EDBs).In this work,we study the leakage of OPE and ORE and their forward *** propose generic yet powerful file-inject ion attacks(FI As)on OPE/ORE,aimed at the situations of possessing order by and range *** FI As only exploit the ideal leakage of OPE/ORE(in particular,no need of data denseness or frequency).We also improve their efficiency with the frequency statistics using a hierarchical idea such that the high-frequency values will be recovered more *** conduct some experiments on real datasets to test the performance,and the results show that our FI As can cause an extreme hazard on most of the existing OPEs and OREs with high efficiency and 100%recovery *** then formulate forward security of ORE,and propose a practical compilation framework for achieving forward secure ORE to resist the perniciousness of *** compilation framework can transform most of the existing OPEs/OREs into forward secure OREs,with the goal of minimizing the extra burden incurred on computation and *** also present its security proof,and execute some experiments to analyze its *** proposed compilation is highly efficient and forward secure.

关键词： order-revealing encryption order-preserving encryption file-injection attack forward security