中国国际时装周2020春夏系列(Ⅱ)

以“Keep Real”为主题的2020春夏系列中国国际时装周,寓意“保持真我,自在随风”,以此主题致敬建国70年来中国时尚产业的飞速发展,亦致敬中国服装设计师始终如一的坚持。中国服装设计师协会借助中国国际时装周平台启动“城市之光”时尚名城造星计划,本次携手北京、深圳、大连的政府及时尚机构,发掘代表城市的优秀青年设计师。     

酶法提取大米蛋白的研究

采用4种蛋白酶水解大米蛋白,比较提取率后得出碱性蛋白酶为最优酶.采用单因素实验分别考察温度、加酶量、料液比、水解时间和pH对该酶提取大米蛋白的影响.通过正交实验确定了最佳工艺条件为:温度60℃、加酶量(E/S)1.5%、pH9.5、料液比1:6、水解时间4h.在此条件下,蛋白质的提取率可达76.42%.     

响应面法优化高产海藻糖菌株的培养条件

采用响应面方法对高产海藻糖的酵母茵的培养条件进行了优化.通过Plackett-Burman(PB)设计法,评价了不同温度、pH、接种量、葡萄糖浓度、酵母抽提物浓度、无机氮源(NH4)2So4浓度和摇床转速等7个因素对海藻糖产量的影响.筛选出葡萄糖浓度、酵母抽提物浓度以及接种量为海藻糖生产过程中的主要影响因素,而其它因素对生产海藻糖的影响不显著.然后用旋转中心组合设计及响应面分析法确定了主要因素的最优条件,分别为葡萄糖浓度21.2 g/L,酵母抽提物浓度5.25 g/L,接种量10%.     

梳棉工艺对单纱强力影响的灰色GM(0,N)预测模型

梳棉工序中刺辊与给棉罗拉、锡林与刺辊、锡林与道夫的线速度比配合不当将会造成纤维的损伤,影响纱线强力.运用灰色关联分析刺辊与给棉罗拉、锡林与刺辊、锡林与道夫的线速度比与单纱强力的关联度,并且建立GM(0,N)单纱强力的预测模型.结果表明:刺辊与给棉罗拉、锡林与刺辊、锡林与道夫的线速度比均影响单纱强力,其关联度分别为0.7...     

He－Ne激光多方式出光在针灸医疗上应用研究

介绍了Ｈｅ－Ｎｅ激光器多方式出光的原理和应用。其中干涉出光使同一出射激光束在不损失能量的条件下，由１次只照射１个人体穴位变成同时照射几个人体穴位，缩短了１人次的治疗时间，提高了治疗效果。     

氮,磷,EDTA铁,锰对旋链角毛藻生长的影响

采用正交实验的方法,研究了N,P,Fe-EDTA,Mn对赤潮生物旋链角毛藻生长的影响.结果表明,磷和络合铁对该藻的细胞密度、生长率和世代时间均有显著影响,得出旋链角毛藻适合生长的磷浓度范围为l mmol/L～2 mmol/L,铁浓度范围为5 μmol/L～10μmoL/L,最优培养液组合为1 mmol/L氮浓度、2 mmoL/L磷浓度和10 μmoL/L铁浓度.其影响主次因素为:磷>络合铁>氮>锰.     

洋葱提取液对鲜切马铃薯褐变的影响

使用洋葱的磷酸缓冲溶液提取液对马铃薯PPO酶活抑制率以及鲜切片贮藏保鲜进行了研究。结果表明，洋葱提取液抑制马铃薯PPO酶活的效果分别达到了34．2％和59.3％，且经100℃水浴加热的洋葱提取液对马铃薯PPO酶活的抑制效果优于新鲜的洋葱提取液。在贮藏实验中洋葱提取物通过对贮藏过程中鲜切薯片的硬度、色度和PPO酶活力变化的测定，初步证实了洋葱提取液具有防褐变效果。     

Pr0．5 La0．2 Sr0．3 MnO3的电磁性能及其庞磁电阻效应

锰氧化合物在计算机硬盘和磁头等领域有着广泛的应用。本实验用高温烧结法制备了半掺杂锰氧化合物Pr_(0.5)La_(0.2)Sr_(0.3)MnO_3陶瓷,测试结果表明,在温度从5K增加到300K的过程中,样品依次由反铁磁绝缘体转变为铁磁半导体、铁磁金属、顺磁半导体。在发生反铁磁-铁磁和铁磁-顺磁两种转变温度处,样品在较低的外加磁场作用下,都表现出了较强的庞磁电阻效应。     

弱BR0代数

探讨BR0代数中不可交换的t模。研究了王国俊教授的《非经典数理逻辑》中剩余格部分,结合吴洪博教授所提出的BR0代数,从t模角度切入,限制t模的交换条件。在BR0代数基础上得到了一类更具有一般意义的弱BR0代数,给出了它的性质及等价刻画;并且证明了弱BR0代数类形成一个代数簇,即等式代数簇。提出了一类新的逻辑代数一弱BR0代数,为深入研究BR0代数奠定基础。     

改革开放30年来五金科技成果回顾与分析——国家科学技术奖励工作办公室处长姚昆仑

五金科技创新是五金行业应对金融危机,实现跨越式发展的必由之路.改革开放30年来,五金行业发展迅速,成为世界五金大国.统计分析国家科技成果库中五金行业科技成果数据,可以从中反映出我国五金科技的发展情况.     

DBR0-代数及其弱化形式 LBR0-代数的性质

通过对B R0-代数无序表示形式的再研究,利用逻辑代数中交、并运算对偶的特点以及对偶范畴的思想,从经典代数的角度出发于一般集合上建立了一种对称形式的BR0-代数-DBR0-代数。证明了DBR0-代数是BR0-代数的又一新的无序表示形式,它将BR0-代数中的序关系蕴涵于基本运算·和→之中。根据DBR0-代数的形式提出了一种弱化的BR0-代数-LBR0-代数,并证明了LBR0-代数与正则FI代数是同一代数结构。     

不同施肥方式对植烟土壤有效氮、烟株氮累积量和速率的影响

在鄂西南植烟土壤上研究了不同施肥方式对土壤有效氮、烟株氮累积量以及氮累积速率的影响。结果显示,在不栽烟情况下,施肥后40 d内肥料养分损失完毕,60 d后土壤有机氮矿化量高于有效氮损失量,土壤有效氮出现净累积;全生育期覆膜方式下移栽后63 d内化肥处理(D)土壤有效氮明显高于有机无机配施处理(G),烟株氮累积和土壤有效氮下降成显著负相关,且G处理相关程度(-0.935)高于D处理(-0.661);前期覆膜团棵揭膜方式下,移栽后42 d内化肥处理(E)土壤有效氮明显高于有机无机配施处理(F),烟株氮累积量和累积速率F处理均高于E处理;提前施肥起垄方式下,化肥处理(I)和有机无机配施处理(H)土壤有效氮变化基本一致且烟株氮累积量和累积速率H处理均高于I处理。不论何种施肥方式,移栽后前期化肥处理土壤有效氮含量明显高于有机无机配施处理,而烟株氮累积则相反,证明施用有机肥可以使烟株对氮素吸收累积高峰提前,且提高烟株氮累积量和氮累积速率。提前施肥可明显弱化不同肥料处理之间土壤有效氮的差异。     

金戈铁马忆往昔

刀光剑影的古战场,自古成就了多少英雄豪杰扬名立万,也让不少志士青年马革裹尸还。那些厌倦了你死我活的战场拼杀的老将,偶尔也会在梦里梦到那些让他们势血沸腾的日子。     

N,N,N-trimethyl chitosan nanoparticles as a vitamin carrier system

There is considerable interest in incorporating stabilized vitamins into biopolymeric nanoparticles, especially in the development of carriers and active systems for pharmaceutical and food applications. Amongst biopolymer, chitosan is highly desirable owing to its good biocompatibility, biodegradability and ability to be chemically modified. In this paper, nanoparticles from three kinds of water-soluble derivative chitosan (N,N,N-trimethyl chitosan, TMC) have successfully been synthesized by ionic gelation with tripolyphosphate (TPP) anions. Combinations of concentrations of TMC and TPP have resulted in nanoparticles with varying sizes for which the capability for loading with vitamins was investigated. Zeta potential measurement and particle size analysis demonstrated that the size of the nanoparticles was optimized (196 ± 8 nm) when the lowest TMC and TPP amounts were used, i.e., 0.86 mg mL⁻¹ and 0.114 mg mL⁻¹ respectively. As the TMC and/or the TPP concentrations increase, the resulting size of the nanoparticles increases considerably. Three different vitamins (B9, B12 and C) were tested as additives and the final system characterized in relation to size, morphology, spectroscopic and zeta potential properties. In general, the incorporation of vitamins increased all the TMC–TPP original nanoparticle sizes, reaching a maximum diameter of 534 ± 20 nm when loaded with vitamin C. The presence of vitamins also decreases the zeta potential, with one exception observed when using vitamin C. The preliminary results of this study suggested that all TMC/TPP nanoparticles can be successfully used as a stable medium to incorporate and transport vitamins, with potential applications in foodstuffs.     

一致U0-凸算子与一致U0-凹算子的一个注记

建立了一致 U0 -凸算子与一致 U0 -凹算子之间的一种重要联系 ,证明了 A是一致 U0 -凸算子的充分必要条件是算子 B为一致 U0 -凹算子 ,且满足　 Bx =‖ x‖ 2U0 A x‖ x‖ 2U0x≠θ,x∈ Kθ x =θ     

Microstructure and rheology of phase-separated gels of gelatin + oxidized starch

We report on small-deformation rheology and confocal microscopy at 24 °C of high-sugar gel samples based on an aqueous mixture of gelatin + oxidized (non-gelling) starch exhibiting thermodynamic incompatibility. Using a standard protocol involving the heating of previously rapidly quenched samples at a fixed holding temperature (24–60 °C) for a fixed time (from 20 s to 30 min), gel samples of different storage modulus and degrees of spinodal-type phase separation were systematically generated. The developing time-dependent modulus of the gelatin gel was found to be sensitive to the extent of gelatin crosslinking as influenced by the nature of the thermal processing conditions. Under identical processing conditions, a gradual increase in starch content gave gels of lower elastic modulus and increased degree of microscopic phase separation. Taken all together, our results indicate that the gel rheology is determined by a subtle combination of overall system composition and temperature/time processing history. We conclude that the mechanical properties of this mixed biopolymer system are not directly deducible from the extent of phase separation observed microscopically without detailed additional information concerning sample preparation and treatment conditions.     

Flavour differences of cooked longissimus muscle from Chinese indigenous pig breeds and hybrid pig breed (Duroc × Landrace × Large White)

The objectives of this study were to investigate the flavour quality and volatile aroma compounds of cooked longissimus muscle from five typical Chinese indigenous pig breeds: Lantang (LT), Dahuabai (HB), Laiwu (LW), Rongchang (RC), Tongcheng (TC) and typical hybrid pig breed Duroc × Landrace × Large White (DLW). The chemical compositions of the main meat flavour precursors of the longissimus muscle from all six breeds were also examined. Distinct differences in amino acid composition and fatty acid composition of longissimus muscle, between the breeds, were observed. Among all six breeds, LW and RC had the highest intramuscular fat content and the lowest crude protein content; DLW had the lowest longissimus muscle fat content and the highest crude protein content. One-way analysis of variance showed that 23 volatile compounds were significantly affected by breed. Sensory analysis indicated that cooked longissimus muscle from DLW had the lowest pork flavour intensity and flavour-liking, compared with the Chinese indigenous breeds. LW and HB showed the highest pork flavour intensity and flavour-liking in cooked longissimus muscle.     

应用氢气碰撞反应气-电感耦合等离子体质谱仪同时分析不锈钢食具容器的8种重金属迁移量

建立了应用氢气碰撞反应气-电感耦合等离子质谱技术测定不锈钢食具容器中9种重金属迁移量的新方法。利用氢气作为反应气的动态反应池(DRC)技术,达到去除质谱干扰的作用。在优化的实验条件下,不锈钢食具容器的Pb、Cd、Ni、Cr、As、Al、Cu、Zn 8种可迁移重金属,各重金属元素的标准曲线的线性关系良好,相关系数在0.9992-1.0000,检出限在0.043 ug/L-1.43ug/L,加标回收率在85.1%-105.1%,RSD在2.8%-7.6%,表明该方法具有良好的精密度和准确性,适用于不锈钢食具容器种可迁移重金属的检测分析。