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Synthesis and Self-assembly of a Linear Coil-Coil-Rod ABC Triblock Copolymer

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Chinese Journal of Polymer Science 2014年第11期32卷 1524-1534页

作者： Ling-ying Shi Yu Pan qi-kai zhang Yu Zhou Xing-he Fan 沈志豪 Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

An interesting order-order transition between two different complex nanostructures was observed in a new liquid crystalline linear coil-coil-rod ABC triblock copolymer（tri BCP）. First, the ABC tri BCP, poly（dimethylsiloxane）-bpolystyrene-b-poly{2,5-bis[（4-methoxyphenyl）oxycarbonyl]styrene}（PDMS-b-PS-b-PMPCS）, was synthesized through sequential atom transfer radical polymerization. The degrees of polymerization of PDMS, PS, and PMPCS blocks are 58, 159, and 106, and the corresponding volume fractions of PDMS, PS, and PMPCS are 0.09, 0.29, and 0.62, respectively. The phase behaviors of the PDMS-b-PS diblock copolymer precursor and the final triblock copolymer were studied by smallangle X-ray scattering, one-dimensional wide-angle X-ray scattering, and transmission electron microscopy experiments. The PDMS-b-PS precursor self-assembles into hexagonally packed cylinders with a relatively small periodic size after thermal annealing. When the triblock copolymer is annealed at a relatively low temperature（120 ○C） at which the PMPCS block is in the amorphous state, the tri BCP forms core-shell hexagonally packed cylinders（CSH） with a relativly large periodic size. After the tri BCP is annealed above 140 ○C at which the PMPCS block transforms to the liquid crystalline（LC） phase, the nanophase-separated structure transforms to a three-phase four-layer lamellar structure（LAM-3P4L）. Thus, accompanied with the transition of the PMPCS blocks from the amorphous state to the LC phase, the order-order transition from CSH to LAM-3P4 L occurs in the PDMS-b-PS-b-PMPCS ABC tri BCP.

关键词： Coil-coil-rod triblock copolymer Self-assembly Order-order transition Liquid crystalline polymer Complex nanostructures.

GAM:A GPU-Accelerated Algorithm for MaxRS Queries in Road Networks

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Journal of Computer Science & Technology 2022年第5期37卷 1005-1025页

作者： Jian Chen kai-qi zhang Tian Ren Zhen-qing Wu Hong Gao School of Computer Science and Technology Harbin Institute of TechnologyHarbin150001China

In smart phones,vehicles and wearable devices,GPS sensors are ubiquitous and collect a lot of valuable spatial data from the real *** a set of weighted points and a rectangle r in the space,a maximizing range sum(MaxRS)query is to find the position of r,so as to maximize the total weight of the points covered by r(i.e.,the range sum).It has a wide spectrum of applications in spatial crowdsourcing,facility location and traffic *** of the existing research focuses on the Euclidean space;however,in real life,the user’s moving route is constrained by the road network,and the existing MaxRS query algorithms in the road network are *** this paper,we propose a novel GPU-accelerated algorithm,namely,GAM,to tackle MaxRS queries in road networks in two phases *** phase 1,we partition the entire road network into many small cells by a grid and theoretically prove the correctness of parallel query results by grid shifting,and then we propose an effective multi-grained pruning technique,by which the majority of cells can be pruned without further *** phase 2,we design a GPU-friendly storage structure,cell-based road network(CRN),and a two-level parallel framework to compute the final result in the remaining ***,we conduct extensive experiments on two real-world road networks,and the experimental results demonstrate that GAM is on average one order faster than state-of-the-art competitors,and the maximum speedup can achieve about 55 times.

关键词： road network maximizing range sum GPU acceleration pruning strategy

Implementation of a cusp-like for real-time digital pulse shaper in nuclear spectrometry

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Nuclear Science and Techniques 2017年第7期28卷 79-84页

作者： Jun Liu Jian Yang Guo-qiang Zeng kai-qi zhang Shi-Long Wei Liang-Quan Ge Chengdu University of Technology Chengdu 610059 China

Pulse shaping,which improves signal-to-noise ratio excellently,has been extensively used in nuclear signal *** paper presents a cusp-like pulse-shaping technique developed through the recursive difference equation in time *** can be implemented in field programmable gate array hardware *** flat-topped cusp-like shaper is developed to optimize the time constant of pulse shaping and reduce the influence of ballistic *** methods of both baseline restoration and pile-up rejection are *** ^(137)Cs energy spectra measured with the digital cusp-like shaper are 6.6% energy resolution,while those by traditional analog pulse shaper are 7.2% energy resolution,under the same *** technique offers flexibility,too,in adjusting the pulse shaper parameters.

关键词：脉冲整形器现场可编程门阵列能量分辨率尖点实时谱仪递归差分方程整形技术

Secondary Structurc in Solution of an Analog of Salmon Calcitonin:[Val^1, Ala^7]sCT

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Chinese Chemical Letters 1999年第7期10卷 555-558页

作者： Bin YANG Hou Li JIANG Zhen kai DING qi kai zhang(Beijing Institute of Pharmacology and Toxicology Beijing 100850National Center of Biomedical Analysis. Beijing 100850) Beijing Inst. Pharmacol. Toxicol. Beijing 100850 China Natl. Center of Biomedical Analysis Beijing 100850 China

Secondary structure of [Val. Ala]sCT- an analog of salmon calcitonin (sCT) not containing an N-terminal disultide bridge. was investigated by circular dichroism (CD) and Fourier-transform intrared spectroscopy (FTIR) methods. Both CD and FTIR results show that the main contbrmational structure of [Val Ala']sCT in aqueous solution is random coil structure. while in trifluorethanol (TFE) it displays a strong α-helical structure. The relationship between the biological activity and the conformational structure of [Val, Ala] sCT is als0 discussed.

关键词： Salmon calcitonin analog CD FTIR peptide secondary structure

A novel approach to predict green density by high-velocity compaction based on the materials informatics method

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 194-201页

作者： kai-qi zhang Hai-qing Yin Xue Jiang Xiu-qin Liu Fei He Zheng-hua Deng Dil Faraz Khan qing-jun Zheng Xuan-hui Qu Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beijing Key Laboratory of Materials Genome Engineering Beijing Laboratory of Metallic Materials and Processing for Modern Transportation School of Mathematics and Physics University of Science and Technology Beijing Chongqing Engineering Technology Research Center for Light Alloy and Processing Department of Physics University of Science and Technology Bannu Kennametal Inc

High-velocity compaction is an advanced compaction technique to obtain high-density compacts at a compaction velocity of ≤10 m/s. It was applied to various metallic powders and was verified to achieve a density greater than 7.5 g/cm^3 for the Fe-based powders. The ability to rapidly and accurately predict the green density of compacts is important, especially as an alternative to costly and time-consuming materials design by trial and error. In this paper, we propose a machine-learning approach based on materials informatics to predict the green density of compacts using relevant material descriptors, including chemical composition, powder properties, and compaction energy. We investigated four models using an experimental dataset for appropriate model selection and found the multilayer perceptron model worked well, providing distinguished prediction performance, with a high correlation coefficient and low error values. Applying this model, we predicted the green density of nine materials on the basis of specific processing parameters. The predicted green density agreed very well with the experimental results for each material, with an inaccuracy less than 2%. The prediction accuracy of the developed method was thus confirmed by comparison with experimental results.

关键词： powder metallurgy high-velocity compaction green density data mining multilayer perceptron

Advances of embedded resistive random access memory in industrial manufacturing and its potential applications

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International Journal of Extreme Manufacturing 2024年第3期6卷 175-214页

作者： Zijian Wang Yixian Song Guobin zhang qi Luo kai Xu Dawei Gao Bin Yu Desmond Loke Shuai Zhong Yishu zhang College of Integrated Circuits Zhejiang UniversityHangzhouZhejiang 3112000People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310027People’s Republic of China Department of Science Mathematics and TechnologySingapore University of Technology and DesignSingapore 487372Singapore Guangdong Institute of Intelligence Science and Technology HengqinZhuhai 519031People’s Republic of China

Embedded memory,which heavily relies on the manufacturing process,has been widely adopted in various industrial *** the field of embedded memory continues to evolve,innovative strategies are emerging to enhance *** them,resistive random access memory(RRAM)has gained significant attention due to its numerousadvantages over traditional memory devices,including high speed(<1 ns),high density(4 F^(2)·n^(-1)),high scalability(~nm),and low power consumption(~pJ).This review focuses on the recent progress of embedded RRAM in industrial manufacturing and its *** provides a brief introduction to the concepts and advantages of RRAM,discusses the key factors that impact its industrial manufacturing,and presents the commercial progress driven by cutting-edge nanotechnology,which has been pursued by manysemiconductor ***,it highlights the adoption of embedded RRAM in emerging applications within the realm of the Internet of Things and future intelligent computing,with a particular emphasis on its role in neuromorphic ***,the review discusses thecurrent challenges and provides insights into the prospects of embedded RRAM in the era of big data and artificial intelligence.

关键词： embedded resistive random access memory industrial manufacturing intelligent computing advanced process node

Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： Yong qi Shufen zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic *** can produce one or more temporary shapes through nanoscale deformation,memorizing current *** can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural *** porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and ***,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and *** primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface *** aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of ***,perspectives on future research directions and applications are also *** is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Fermented soybean meal improved laying performance and egg quality of laying hens by modulating cecal microbiota,nutrient digestibility,intestinal health,antioxidant and immunological functions

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Animal Nutrition 2024年第3期18卷 309-321页

作者： Uchechukwu Edna Obianwuna Lingling Huang Haijun zhang Jing Wang Guanghai qi kai qiu Shugeng Wu National Engineering Research Center of Biological Feed Institute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081China Wilmar(Shanghai)Biotechnology Research&Development Center Co. Ltd.Shanghai 200137China

Antinutritional factors in feedstuffs may limit their utilization in livestock production,but fermentation process can be used to improve feed quality;however,studies on fermented soybeans for laying hens remain *** investigated the effect of fermented soybean meal(FSBM)at various inclusion levels as a partial replacement for soybean meal(SBM)on egg production,egg quality,amino acid digestibility,gut morphology and microbiota,antioxidant capacity and immune response of young laying hens.A total of 360 Hy-line Brown laying hens aged 18 weeks were selected and divided into 5 groups of 6 replicates each and 12 birds per *** control group received a basal diet while the trial group received the basal diet with FSBM included at 2.5%,5.0%,7.5%and 10.0%,respectively,for 12 *** findings revealed that the nutritional value of FSBM was higher compared to that of SBM in terms of reduced content of trypsin inhibitors and increased contents of crude protein,amino acids and *** enhanced egg production(P<0.05),feed-to-egg ratio(P<0.05),and albumen quality(albumen height and Haugh unit)(P<0.05).Furthermore,FSBM improved apparent fecal amino acid digestibility(P<0.05),gut morphology(increased villus height,villus width,villus height-to-crypt depth ratio and decreased crypt depth)(P<0.05),antioxidant capacity(reduced malondialdehyde and increased catalase,total superoxide dismutase,glutathione peroxidase and total antioxidant capacity)(P<0.05)and immune function(increased concentrations of IgG,IgA,and IgM;increased levels of transforming growth factor beta and Toll-like receptor 2;and reduced levels of interleukin 1βand tumor necrosis factor alpha)(P<0.05).Further analysis showed that FSBM altered the composition of the gut microbiota favoring beneficial *** findings suggest that probiotic fermentation improved the nutritional value of *** inclusion of FSBM in the diets of laying hens at 2.5%or 5.0%improved amino acid digestibility,gut

关键词： Fermented soybean meal Laying hen Egg production Egg quality Immune response

Sound event localization and detection based on deep learning

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Journal of Systems Engineering and Electronics 2024年第2期35卷 294-301页

作者： ZHAO Dada DING kai qi Xiaogang CHEN Yu FENG Hailin School of Mathematics and Statistics Xidian UniversityXi’an 710071China Science and Technology on Near-Surface Detection Laboratory Wuxi 214035China

Acoustic source localization(ASL)and sound event detection(SED)are two widely pursued independent research *** recent years,in order to achieve a more complete spatial and temporal representation of sound field,sound event localization and detection(SELD)has become a very active research *** paper presents a deep learning-based multioverlapping sound event localization and detection algorithm in three-dimensional ***-Mel spectrum and generalized cross-correlation spectrum are joined together in channel dimension as input *** features are classified and regressed in parallel after training by a neural network to obtain sound recognition and localization results *** channel attention mechanism is also introduced in the network to selectively enhance the features containing essential information and suppress the useless ***,a thourough comparison confirms the efficiency and effectiveness of the proposed SELD *** experiments show that the proposed algorithm is robust to reverberation and environment and can achieve higher recognition and localization accuracy compared with the baseline method.

关键词： sound event localization and detection(SELD) deep learning convolutional recursive neural network(CRNN) channel attention mechanism