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Known-key distinguishers on type-1 Feistel scheme and near-collision attacks on its hashing modes

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Frontiers of Computer Science 2014年第3期8卷 513-525页

作者： Le DONG Wenling WU Shuang WU jian zou College of Mathematics and Information Science Henan Normal University Xinxiang 453007 China Institute of Software Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100149 China

We present some known-key distinguishers for a type-1 Feistel scheme with a permutation as the round function. To be more specific, the 29-round known-key truncated differential distinguishers are given for the 256-bit type-1 Feistel scheme with an SP （substitution-permutation） round function by using the rebound attack, where the S-boxes have perfect differential and linear properties and the linear diffusion layer has a maximum branch number. For two 128-bit versions, the distinguishers can be applied on 25- round structures. Based on these distinguishers, we construct near-collision attacks on these schemes with MMO （Matyas- Meyer-Oseas） and MP （Miyaguchi-Preneel） hashing modes, and propose the 26-round and 22-round near-collision attacks for two 256-bit schemes and two 128-bit schemes, respectively. We apply the near-collision attack on MAME and obtain a 26-round near-collision attack. Using the algebraic degree and some integral properties, we prove the correctness of the 31-round known-key integral distinguisher proposed by Sasaki et al. We show that if the round function is a permutation, the integral distinguisher is suitable for a type-1 Feistel scheme of any size.

关键词： known-key block cipher generalized Feistel scheme type-1 rebound attack integral distinguisher algebraic degree

Enantiomer-selective Living Polymerization of rac-Phenyl Isocyanide Using Chiral Palladium Catalyst

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Chinese Journal of Polymer Science 2018年第7期36卷 799-804页

作者： jian Huang Ling Shen Hui zou Na Liu Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Hefei University of Technology and Anhui Key Laboratory of Advanced Catalytic Materials and Reaction Engineering

We report the polymerization of phenyl isocyanides with the chiral palladium（II） initiating system. The resulting polymers with optically active properties were obtained by polymerization of the racemic isocyanide monomer （rac-1）, and enantiomerically unbalanced polymerization of the monomer was found, providing substantial evidence for the enantiomer-selective polymerization of rac- 1 mediated through chiral catalyst. A comparison between the enantiomerically pure monomers, 4-isocyanobenzoyl-L-alanine decyl ester （1 s） and 4-isocyanobenzoyl-D-alanine decyl ester （1 r）, revealed a drastic discrepancy in the reactivity ratio of their homopolymerizations. It turned out that the monomer reactivity ratio of ls was higher than that of lr with chiral ligands. The results clearly demonstrated the inclination for incorporation of the ls enantiomer during the polymerization process and thus resulted in the enantiomer-selective polymerization in this system. The effects of the catalyst chirality on the optically active properties of polymerization were investigated, and it was concluded that the formation of higher-ordered conformation with a handed helicity might be attributed to the chiral induction of chiral palladium（II） catalyst. Moreover, the polymers obtained through the enantiomer-selective polymerization of the enantiomerically pure monomer were with a significant improvement of the optical activity if the chirality of the monomer and the catalyst matched with each other.

关键词： Enantiomer-selective polymerization Kinetic resolution Chiral sulfinamide bisphosphine Polyisocyanides Living polymerization

Speciation characterization and coagulation of poly-silica-ferric-chloride:The role of hydrolyzed Fe(Ⅲ) and silica interaction

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Journal of Environmental Sciences 2011年第5期23卷 749-756页

作者： jian Shi Yan Zhang Kaiyun zou Feng Xiao Nantong University Nantong 226007 China. E-mail: shijianchuyu @ *** Key Laboratory of Environmental Water Chemistry Ecological Environment Research Center of Chinese Academy of Science Beijing 100085 China

The highly efficient inorganic polymer flocculants （IPFs） of the ferric-silica system is a new and promising coagulant. Interactions between ferric species and silica play a large part in the coagulation of suspensions. These effects are quite distinct from those associated with polymeric or colloid silica. However, although these species are key to coagulation efficiency, they have not been comprehensively discussed. A new type of coagulant, poly-silica-ferric-chloride （PFSC）, was synthesized by co-polymerization and characterized by time complexation spectroscopy and photon correlation spectroscopy. Compared with traditional ferric salt, the results indicated that PFSC had a higher molecular weight, lesser positive charge, lower Feb and higher Fec. The higher the Si/Fe ratio, the higher the silica and lower the silicac found. The PFSC with appropriate polysilica acid not only obtained better coagulation/flocculation efficiency in turbidity removal, enhanced the flocculation index （FI） and provided less residual ferric, it also lowered water treatment costs compared to traditional ferric salt. Results showed that PFSC could remove colloid particles in water by charge neutralization and sweeping, adsorption bridging mechanism.

关键词： coagulation inorganic polymer flocculant PFSC species distribution residual ferric

Simulation of turbulent combustion in DLR Scramjet

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1053-1058页

作者： zou jian-feng ZheNG Yao LIU Ou-zi School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China

Turbulent combustion in a DLR (German Aerospace Center) Scramjet engine was simulated using the newly-proposed Partially Resolved Numerical Simulation (PRNS) procedure. The PRNS procedure uses temporal filtering to define large-scale turbulence, and the model developed to account for unresolved scales is grid independent. No problem about inner commutation error and inconsistencies will arise from the PRNS, while such issues are of concern in traditional Large Eddy Simulation (LES) methods. The mean results have good agreement with the experiment data and the flow structures with small scales are well resolved.

关键词： Scramjet Turbulent combustion Unstructured grid Finite volume method

基于钯纳米颗粒导电沟道的室温型氢气传感器的研究

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传感技术学报 2024年第1期37卷 16-21页

作者：涂建鑫邹杰孙靖远张文冰毕春跃谢光忠简家文宁波大学信息科学与工程学院浙江宁波315211 电子科技大学光电科学与工程学院四川成都610054 浙江万里学院大数据与软件工程学院浙江宁波315100

随着氢能的广泛应用,检测氢气(H_(2))泄漏十分必要。采用溶剂热法合成钯(Pd)纳米颗粒,结合旋涂法从极大程度上简化了覆盖敏感层工艺,在利用微机电系统(MEMS)工艺制备的硅基金(Au)叉指电极上研究了基于“氢致Pd晶格膨胀效应(HILE)”的裂... 详细信息

随着氢能的广泛应用,检测氢气(H_(2))泄漏十分必要。采用溶剂热法合成钯(Pd)纳米颗粒,结合旋涂法从极大程度上简化了覆盖敏感层工艺,在利用微机电系统(MEMS)工艺制备的硅基金(Au)叉指电极上研究了基于“氢致Pd晶格膨胀效应(HILE)”的裂结式H_(2)传感器的敏感特性,为低成本批量化制备室温型氢气传感器提供了可行性研究。结果表明该传感器对H_(2)的响应值与Pd纳米颗粒在基底上的覆盖率密切相关:覆盖率在一定范围内越大,响应值越小。在室温下,该类传感器对500×10^(-6)~2500×10^(-6)H_(2)表现出了较快的响应速度:响应时间在5 s左右,恢复时间在25 s左右,具有较高的响应值:在2500×10^(-6)H_(2)气氛下高达83%,有较好的选择性和稳定性。

关键词：叉指电极氢气传感器 Pd纳米颗粒氢致晶格膨胀

DVB-S2 inner receiver design for broadcasting mode

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 28-35页

作者： YANG jian-xiao WANG Kuang zou Zhi-yong Institute of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China Guoxin Co Ltd Hangzhou 310027 China

This paper details on the design of DVB-S2 receivers which is compliant with the broadcasting mode. Special at-tention is paid to the specific receiver functions necessary to demodulate the received signal. To show the system performance we consider the design of a complete receiver consisting of timing recovery unit, frame synchronization unit, frequency recovery unit and phase recovery unit. The system is easier to hardware implementation comparing with that provided in (ETSI, 2005; Sun et al., 2004). After the performance of the algorithms is analyzed and a quantitative result is given, this allows us to draw conclusions concerning the achievable system performance under realistic complexity assumptions.

关键词： DVB-S2 Timing recovery Frame synchronization Frequency recovery Phase recovery

饲粮添加不同比例小麦对凤达1号产蛋高峰期蛋鸡生产性能、蛋品质、血清生化指标、小肠形态以及盲肠菌群的影响

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动物营养学报 2024年第4期36卷 2356-2369页

作者：牟天铭李燕苗洒洒简华锋董信阳邹晓庭浙江大学动物科学学院饲料科学研究所生物饲料安全与污染防控国家工程实验室浙江大学动物分子营养学教育部重点实验室农业农村部(华东)动物营养与饲料重点实验室浙江省饲料与动物营养重点实验室杭州310058

本试验旨在研究饲粮中添加不同比例小麦对凤达1号产蛋高峰期蛋鸡生产性能、蛋品质、血清生化指标、小肠形态结构以及盲肠菌群的影响。试验选取生长良好、体况相似的300日龄凤达1号蛋鸡768只,随机分为4个组,每组6个重复,每个重复32只鸡... 详细信息

本试验旨在研究饲粮中添加不同比例小麦对凤达1号产蛋高峰期蛋鸡生产性能、蛋品质、血清生化指标、小肠形态结构以及盲肠菌群的影响。试验选取生长良好、体况相似的300日龄凤达1号蛋鸡768只,随机分为4个组,每组6个重复,每个重复32只鸡。对照组饲喂玉米-豆粕型基础饲粮,试验组以对照组饲粮营养水平为基础,分别在饲粮中添加20%、40%和60%小麦,并根据小麦用量添加适宜比例的复合型小麦酶,同时相应调整饲粮配方以保证各组饲粮能量和蛋白质水平基本一致。预试期7 d,正试期49 d。结果表明:1)与对照组相比,添加20%、40%和60%小麦对产蛋高峰期蛋鸡各主要生产性能指标均无显著影响(P>0.05)。2)与对照组相比,添加不同比例小麦显著降低蛋黄颜色(P0.05)。5)与对照组相比,40%小麦组盲肠菌群α多样性和β多样性均无显著差异(P>0.05);在门水平上,添加40%小麦显著提高盲肠脱硫杆菌门和WPS-2相对丰度(P<0.05)。综上所述,饲粮添加不同比例小麦可以提高凤达1号产蛋高峰期蛋鸡的蛋壳强度和蛋壳厚度,降低蛋鸡血清脂质含量,改善蛋鸡营养代谢;在本试验条件下,凤达1号产蛋高峰期蛋鸡饲粮中添加40%小麦较为适宜。

关键词：小麦产蛋高峰期蛋鸡生产性能蛋品质血清生化指标小肠形态结构盲肠菌群

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催化重整过程苯-甲苯分离体系的模拟与优化

石油化工 2024年第9期53卷 1302-1308页

作者：张广彤韩德求许凌子张健邹雄董宏光辽宁石油化工大学石油化工学院辽宁抚顺113001 黄河三角洲京博化工研究院有限公司山东滨州256600 大连理工大学化工学院辽宁大连116033

针对催化重整装置中的苯-甲苯分离体系能量利用率低的问题,采用差压热耦合精馏技术及热泵精馏技术提高体系的能量利用率,并在差压热耦合精馏单元与热泵精馏单元之间进行热集成,充分利用体系中的余热。应用Aspen HYSYS V11流程模拟软件... 详细信息

针对催化重整装置中的苯-甲苯分离体系能量利用率低的问题,采用差压热耦合精馏技术及热泵精馏技术提高体系的能量利用率,并在差压热耦合精馏单元与热泵精馏单元之间进行热集成,充分利用体系中的余热。应用Aspen HYSYS V11流程模拟软件对优化前后的模型进行模拟计算和分析。模拟结果表明,在产品纯度和收率相同的条件下,采用热泵精馏、差压热耦合精馏和热集成3种节能技术的工艺与原工艺相比可使苯-甲苯分离体系能量节约23.33%。

关键词：热泵精馏差压热耦合精馏热集成工艺模拟优化

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褪黑素对鲜切山药酶促褐变的作用效果

湖南农业大学学报（自然科学版） 2024年第2期50卷 105-112页

作者：胡燕李长滨许美娟袁晓晴邹建河南牧业经济学院食品与生物工程学院河南郑州450046

分别采用1、2、3 mmol/L的褪黑素溶液处理鲜切铁棍山药,以蒸馏水浸泡鲜切山药为对照,室温(25℃)下存放4 d,测定鲜切山药颜色参数(L^(*)、a^(*)、b^(*)、总色差值(ΔE))、多酚氧化酶(PPO)活性、过氧化物酶(POD)活性、苯丙氨酸解氨酶(PAL... 详细信息

分别采用1、2、3 mmol/L的褪黑素溶液处理鲜切铁棍山药,以蒸馏水浸泡鲜切山药为对照,室温(25℃)下存放4 d,测定鲜切山药颜色参数(L^(*)、a^(*)、b^(*)、总色差值(ΔE))、多酚氧化酶(PPO)活性、过氧化物酶(POD)活性、苯丙氨酸解氨酶(PAL)活性、过氧化氢酶(CAT)活性、H2O2含量、脂氧合酶(LOX)活性、丙二醛(MDA)含量、DPPH自由基清除率和ABTS自由基清除率等指标,探究褪黑素对鲜切山药酶促褐变的作用效果。结果表明:褪黑素处理能抑制鲜切山药中PPO、POD、PAL和LOX活性,贮藏4 d时,3 mmol/L褪黑素处理的样品的PPO、POD、PAL和LOX活性比空白对照组的分别小51.6%、65.6%、27.1%、24.6%;褪黑素处理能降低山药中H2O2和MDA含量,贮藏4 d时,3 mmol/L褪黑素处理的样品的H2O2和MDA含量相比空白对照组的分别降低了84.8%和21.0%;褪黑素处理能提高山药中CAT活性,贮藏4 d时,3 mmol/L褪黑素处理的样品的CAT活性为空白对照组的1.96倍;褪黑素处理能提高山药的DPPH和ABTS自由基清除能力,贮藏4 d时,3 mmol/L褪黑素处理样品DPPH和ABTS自由基清除率比空白对照组的分别提高了20.6%、18.7%;褪黑素处理也能有效延缓鲜切山药表面褐变,且其效果具有浓度依赖性,3 mmol/L的褪黑素护色效果最好,贮藏4 d时,3 mmol/L褪黑素处理的样品的L^(*)值比空白对照组大32.5%,a^(*)、b^(*)、ΔE比空白对照组分别小74.0%、50.7%、67.3%;相关分析结果显示,鲜切山药的ΔE与L^(*)、a^(*)、b^(*)、PPO活性、POD活性、PAL活性、H2O2含量和MDA含量均呈极显著相关,与ABTS自由基清除率呈显著相关。

关键词：鲜切山药褪黑素保鲜剂酶促褐变抑制作用