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宁夏贺兰山东麓新引酿酒葡萄品种光合特性比较

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甘肃农业大学学报 2024年第3期59卷 136-144页

作者：杨文忠徐国前张志霞牛敏包小琴宁夏大学农学院宁夏银川750021 宁夏大学食品与葡萄酒学院宁夏银川750021 宁夏葡萄与葡萄酒研究院宁夏银川750021

【目的】对宁夏贺兰山东麓产区种植的酿酒葡萄品种马瑟兰、马尔贝克、小芒森和维欧妮与产区广泛种植的酿酒葡萄品种赤霞珠(CK_(1))和霞多丽(CK_(2))光合生理特征进行研究,筛选适宜该地区种植的新品种。【方法】测定不同品种成熟叶片的... 详细信息

【目的】对宁夏贺兰山东麓产区种植的酿酒葡萄品种马瑟兰、马尔贝克、小芒森和维欧妮与产区广泛种植的酿酒葡萄品种赤霞珠(CK_(1))和霞多丽(CK_(2))光合生理特征进行研究,筛选适宜该地区种植的新品种。【方法】测定不同品种成熟叶片的光响应曲线、CO_(2)响应曲线以及自然条件下的光合日变化特征。【结果】不同品种光合性状存在显著差异,在光响应曲线特征参数中,马瑟兰的最大净光合速率(P_(m))、光饱和点(LSP)显著高于其他品种,CK_(2)的光补偿点(CCP)和暗呼吸速率(R_(d))最大且表观量子效率(AQY)低于其他品种。由CO_(2)响应曲线特征参数可知,维欧妮的羧化效率(CE)、最大光合能力(A_(max))和光呼吸速率(R_(q))均显著高于其他品种,各品种的CO_(2)饱和点(CSP)变化范围在1 109.98~1 318.83μmol/(m^(2)·s)之间,CK_(2)的CO_(2)补偿点(CCP)最高,为77.74μmol/(m^(2)·s),其次为马尔贝克,维欧妮的最低,为60.18μmol/(m^(2)·s)。不同品种的光合日变化中,马瑟兰和马尔贝克的日P_n呈现双峰曲线,并具有明显的“光合午休”现象,其他4个品种的日P_n呈现单峰曲线,其中,维欧妮的净光合速率日均值最大,马尔贝克的最小。【结论】4个新引品种在贺兰山东麓产区的光合适应性均较好,光合能力大小依次是维欧妮>小芒森>CK_(2)>马尔贝克>马瑟兰>CK1。

关键词：酿酒葡萄光合特性光合速率日变化

The Hausdorff Dimension of Sections

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Chinese Annals of Mathematics,Series B 2007年第2期28卷 187-194页

作者： min niu Lifeng XI Department of Mathematics and Mechanics Beijing University of Science and Technology Beijing 100083China Institute of MathematicS Zhejimag Wanli University Ningbo 315100 Zhejiang China

The notion of finite-type open set condition is defined to calculate the Hausdorff dimensions of the sections of some self-similar sets, such as the dimension of intersection of the Koch curve and the line x=α with ... 详细信息

关键词： Hausdorff dimension Self-similar set Section Open set condition

Fuzzy Neural Model for Flatness Pattern Recognition

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Journal of Iron and Steel Research International 2008年第6期15卷 33-38页

作者： JIA Chun-yu SHAN Xiu-ying LIU Hong-min niu Zhao-ping School of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei China

For the problems occurring in a least square method model, a fuzzy model, and a neural network model for flatness pattern recognition, a fuzzy neural network model for flatness pattern recognition with only three-input and three output signals was proposed with Legendre orthodoxy polynomial as basic pattern, based on fuzzy logic expert experiential knowledge and genetic-BP hybrid optimization algorithm. The model not only had definite physical meanings in its inner nodes, but also had strong self-adaptability, anti interference ability, high recognition precision, and high velocity, thereby meeting the demand of high-precision flatness control for cold strip mill and providing a convenient, practical, and novel method for flatness pattern recognition.

关键词： flatness pattern recognition Legendre orthodoxy polynomial genetic-BP algorithm fuzzy neural network

Bifunctional SiC/Si_(3)N_(4) aerogel for highly efficient electromagnetic wave absorption and thermal insulation

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Journal of Advanced Ceramics 2023年第2期12卷 309-320页

作者： Lei WANG Zhixin CAI Lei SU min niu Kang PENG Lei ZHUANG Hongjie WANG State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

SiC ceramics are attractive electromagnetic(EM)absorption materials for the application in harsh environment because of their low density,good dielectric tunable performance,and chemical ***,the performance of current SiC-based materials to absorb EM wave is generally unsatisfactory due to poor impedance ***,we report ultralight SiC/Si3N4 composite aerogels(~15 mg·cm^(−3))consisting of numerous interweaving SiC nanowires and Si3N4 *** were prepared via siloxane pyrolysis and chemical vapor reaction through the template *** optimal aerogel exhibits excellent EM wave absorption properties with a strong reflection loss(RL,−48.6 dB)and a wide effective absorption band(EAB,7.4 GHz)at a thickness of 2 mm,attributed to good impedance matching and multi attenuation mechanisms of waves within the unique network *** addition,the aerogel exhibits high thermal stability in air until 1000℃and excellent thermal insulation performance(0.030 W·m^(−1)·K^(−1)).These superior performances make the SiC/Si_(3)N_(4) composite aerogel promising to become a new generation of absorption material served under extreme conditions.

关键词： bicontinuous network SiC nanowires impedance matching electromagnetic(EM)wave absorption extreme conditions

Resilient Si_(3)N_(4)@SiO_(2)nanowire aerogels for high-temperature electromagnetic wave transparency and thermal insulation

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Journal of Advanced Ceramics 2023年第11期12卷 2112-2122页

作者： Wei Zhang Lei Su De Lu Kang Peng min niu Lei Zhuang Jian Feng Hongjie Wang State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Science and Technology on Advanced Ceramic Fibers and Composites Laboratory National University of Defense TechnologyChangsha 410073China

With the development of aerospace technology,the Mach number of aircraft continues to increase,which puts forward higher performance requirements for high-temperature wave-transparent *** nitrides have excellent mechanical properties,high-temperature stability,and oxidation resistance,but their brittleness and high dielectric constant impede their practical ***,by employing a template-assisted precursor pyrolysis method,we prepared a class of Si_(3)N_(4)@SiO_(2)nanowire aerogels(Si_(3)N_(4)@SiO_(2)NWAGs)that are assembled by Si_(3)N_(4)@SiO_(2)nanowires with diameters ranging from 386 to 631 ***_(3)N_(4)@SiO_(2)NWAGs have low density of 12–31 mg∙cm^(−3),specific surface area of 4.13 m^(2)∙g^(−1),and average pore size of 68.9μ*** properties characterization shows that the aerogels exhibit reversible compressibility from 60%compressive strain and good fatigue resistance even when being compressed 100 times at set strain of 20%.The aerogels also show good thermal insulation performance(0.032 W·m^(−1)∙K^(−1) at room temperature),ablation resistance(butane blow torch),and high-temperature stability(maximum service temperature in air over 1200℃).The dielectric constant and loss of the aerogels are 1.02–1.06 and 4.3×10^(−5)–1.4×10^(−3) at room temperature,*** combination of good mechanical,thermal,and dielectric properties makes Si_(3)N_(4)@SiO_(2)NWAGs promising ultralight wave-transparent and thermally insulating materials for applications at high temperatures.

关键词： electromagnetic wave transparency resilient ceramic aerogels high-temperature stability fire resistance high-temperature resistance

Area Efficient Pattern Representation of Binary Neural Networks on RRAM

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Journal of Computer Science & Technology 2021年第5期36卷 1155-1166页

作者： Feng Wang Guo-Jie Luo Guang-Yu Sun Yu-Hao Wang Di-min niu Hong-Zhong Zheng Center for Energy-Efficient Computing and Applications Peking UniversityBeijing 100871China Pingtouge Alibaba GroupHangzhou 310052China

Resistive random access memory(RRAM)has been demonstrated to implement multiply-and-accumulate(MAC)operations using a highly parallel analog fashion,which dramatically accelerates the convolutional neural networks(CNNs).Since CNNs require considerable converters between analog crossbars and digital peripheral circuits,recent studies map the binary neural networks(BNNs)onto RRAM and binarize the weights to{+1,-1}.However,two mainstream representations for BNN weights introduce patterns of redundant 0s and 1s when dealing with negative *** this work,we reduce the area of redundant 0s and 1s by proposing a BNN weight representation framework based on the novel pattern representation and a corresponding ***,we spilt the weight matrix into several small matrices by clustering adjacent columns ***,we extract 1s'patterns,i.e.,the submatrices only containing 1s,from the small weight matrix,such that each final output can be represented by the sum of several ***,we map these patterns onto RRAM crossbars,including pattern computation crossbars(PCCs)and pattern accumulation crossbars(PACs).Finally,we compare the pattern representation with two mainstream representations and adopt the more area efficient *** evaluation results demonstrate that our framework can save over 20%of crossbar area effectively,compared with two mainstream representations.

关键词： binary neural network(BNN) pattern resistive random access memory(RRAM)

头孢他啶/阿维巴坦对耐碳青霉烯类肺炎克雷伯菌的体外抗菌活性研究

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现代医学 2024年第8期52卷 1197-1204页

作者：郑晓者杨冬晨牛敏杜艳刘淑敏浙江大学医学院附属儿童医院遗传与代谢科浙江杭州310000 昆明医科大学第一附属医院医学检验科云南昆明650032

目的:明确头孢他啶/阿维巴坦(CZA)对耐碳青霉烯类肺炎克雷伯菌的体外抗菌活性。方法:收集昆明医科大学第一附属医院2022年1至12月期间从临床各科室分离的非重复碳青霉烯类耐药肺炎克雷伯菌株(CRKP),分析其临床分布特征和药敏信息;并进... 详细信息

目的:明确头孢他啶/阿维巴坦(CZA)对耐碳青霉烯类肺炎克雷伯菌的体外抗菌活性。方法:收集昆明医科大学第一附属医院2022年1至12月期间从临床各科室分离的非重复碳青霉烯类耐药肺炎克雷伯菌株(CRKP),分析其临床分布特征和药敏信息;并进行耐药基因酶型检测,采用微量肉汤稀释法测定CZA对不同酶型菌株的MIC 50、MIC 90和MIC range;另外,对产NDM型金属酶的CRKP采用微量棋盘稀释法和时间杀菌试验测定CZA联合氨曲南(ATM)体外协同作用。结果:共收集到143株非重复CRKP,标本类型分布以呼吸道标本为主,科室分布主要集中在ICU;药敏结果显示对包括碳青霉烯类在内的多种抗生素耐药率>95%;143株CRKP中bla KPC阳性及bla OXA-48阳性CRKP对CZA敏感率均为100%,bla NDM阳性CRKP对CZA的耐药率为100%,但CZA+ATM联合用药对其具有较强的体外协同抑菌作用。结论:使用CZA治疗CRKP所致感染时,有必要先明确其酶型,为临床抗感染治疗提供用药指导。

关键词：碳青霉烯类耐药肺炎克雷伯菌头孢他啶/阿维巴坦氨曲南协同作用

Polycondensation reaction and its mechanism during lignocellulosic liquefaction by an acid catalyst: a review

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Forestry Studies in China 2011年第1期13卷 71-79页

作者： niu min ZHAO Guang-jie Mehmet Hakki ALMA College of Materials Science and Technology Beijing Forestry University Beijing 100083 R R. China Faculty of Forestry Kahramanmaras Sutcu Imam University Kahramanmaras 46100 Turkey

The increase in the residue content resulting from polycondensation would be adverse to the utilization of lignocellulose and to the quality of products obtained from liquefied lignocellulosic *** yield of the residue formed from liquefaction and the mechanism of polycondensation were reported mainly by Lin,Yamada and *** major products of cellulosic liquefaction are levulinic acid and hydroxymethylfurfural（HMF） derivatives under polyhydric alcohols and phenolated compounds under *** cleavage of the β-O-4 bonds is the major reaction pathway of lignin liquefaction under various liquefying reagents regardless of whether they contain acid catalysts or *** break up compounds by decomposition are polymerized to substances with high molecular weight by polycondensation in lignocellulosic *** molecular weight of condensed residues increases almost linearly as a function of liquefaction time at the later stage of lignocellulosic *** longer the time required,the greater the content of new residue generated by polycondensation during the entire process of *** conclude that the condensed residues may stem from the interaction of degraded lignin and cellulose components in wood or from the products of two major components reacting with liquefying reagents.

关键词： lignocellulose polycondensation mechanism decomposition condensed residues

High-entropy Sm_(2)B_(2)O_(7)(B=Ti,Zr,Sn,Hf,Y,Yb,Nb,and Ta) oxides with highly disordered B-site cations for ultralow thermal conductivity

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Journal of Materials Science & Technology 2022年第24期119卷 182-189页

作者： Liang Xu Lei Su Hongjie Wang Hongfei Gao Pengfei Guo min niu Kang Peng Lei Zhuang Zhiwei Dai State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

Materials with ultralow thermal conductivity and good thermal stability are of great interest in numerous applications such as energy storage and conversion devices,and thermal insulation *** this work,a family of high-entropy Sm_(2)B_(2)O_(7)(B=Ti,Zr,Sn,Hf,Y,Yb,Nb,and Ta) oxides with highly disordered cations on the B-site has been synthesized by introducing large atomic-size mismatch,mass and charge *** tuning the composition,the high-entropy Sm_(2)B_(2)O_(7) oxides can be engineered from pyrochlore to fluorite structure,accompanied with an order-disorder *** pyrochlore Sm_(2)(Nb_(0.2)Sn_(0.2)Ti_(0.2)Y_(0.2)Zr_(0.2))_(2)O_(7) and fluorite Sm_(2)(Nb_(0.2)Ta_(0.2)Y_(0.2)Yb_(0.2)Zr_(0.2))_(2)O_(7) exhibit low thermal conductivities of 1.35 W·m^(-1)·K^(-1) and 1.23 W·m^(-1)·K^(-1),respectively,indicating their good thermal *** addition,the high-entropy fluorite Sm_(2)(Nb_(0.2)Ta_(0.2)Y_(0.2)Yb_(0.2)Zr_(0.2))_(2)O_(7) also shows average thermal expansion coefficient of 10.2 × 10^(-6)℃^(-1) and high-temperature stability even after thermal exposure at 1600 °C in air for 30 *** results indicate that the high-entropy Sm_(2)B_(2)O_(7)(B=Ti,Zr,Sn,Hf,Y,Yb,Nb,and Ta) can be promising candidates for thermal barrier coatings and thermally insulators.

关键词： High-entropy oxides Atomic sizes mismatch Mass and charge disorder Thermal conductivity Thermal barrier coatings materials