微波真空干燥对银耳主要品质影响的研究

研究微波真空干燥技术对银耳主要品质特性的影响。以干制银耳的收缩率、复水比以及多糖含量为指标,探讨微波强度、真空度等因素对银耳干品品质的影响。结果,在真空度一定(-85kPa),微波强度为15W/g的条件下,收缩率最小,为52.92%,复水比最大,达到10.59,而银耳多糖的含量却最低,仅16.34%;当微波强度一定(7.5W/g),真空度为-90kPa的条件下,银耳干品的收缩率、复水比及多糖含量均表现最佳水平。结果表明,为获得高品质的银耳干品,应选择高真空度及合适的微波强度进行干制加工。     

豆渣固体发酵生产灵芝菌丝粉条件优化及三萜化合物含量的测定

利用豆渣代料固体发酵灵芝菌丝粉,结果表明菌丝生长势与菌丝培养温度、培养料/糖比密切相关,培养温度在28℃,料/糖比为100：2,菌丝生长势最强;以单位重量菌丝粉含三萜化合物量为目标函数,利用豆渣培养基培养灵芝菌丝体的最佳条件则为料/糖比为100：2;培养温度为24℃;培养时间为菌丝满瓶后12d.每g菌丝粉三萜化合物含量可达2.44mg.灵芝菌丝特有三萜化合物含量可间接反映菌丝粉中纯菌丝含量及灵芝多糖的含量.     

甲烷存储材料的研究进展

天然气(主要成分甲烷)以其丰富的储量、低廉的价格以及良好的环保效应成为未来最具发展潜力的清洁能源。甲烷的存储是天然气作为车载能源应用的关键技术之一。本文分别介绍了几类存储甲烷材料,包括分子筛、多孔碳材料、金属-有机骨架化合物的功能特点以及近年来储甲烷材料的研究进展,并指出了储甲烷材料的发展方向。     

孕穗期干旱胁迫对水稻部分性状及产量的影响

以8个杂交籼稻品种(组合)为材料,在防雨棚内进行盆栽试验,研究了孕穗期干旱胁迫对水稻部分性状及产量的影响。结果表明:孕穗期干旱胁迫使水稻株高、穗长、一次分枝数、有效穗数、穗实粒数、生物产量、经济产量下降,生育期延长;其中新两优6号、新两优香4号、新两优6380、两优0293经济产量分别位于第一至第四位,产量分别为83.11、82.88、79.08、78.02g/盆,且较正常水分灌溉减产幅度仅为4.3%、5.0%、5.2%、10.3%。因此,新两优6号、新两优香4号、新两优6380、两优0293四个品种适宜在沿淮缺水地区推广种植。     

Towards fully automatic modelling of the fracture process in quasi-brittle and ductile materials: a unified crack growth criterion

Fully automatic finite element （FE） modelling of the fracture process in quasi-brittle materials such as concrete and rocks and ductile materials such as metals and alloys, is of great significance in assessing structural integrity and presents tremendous challenges to the engineering community. One challenge lies in the adoption of an objective and effective crack propagation criterion. This paper proposes a crack propagation criterion based on the principle of energy conservation and the cohesive zone model （CZM）. The virtual crack extension technique is used to calculate the differential terms in the criterion. A fully-automatic discrete crack modelling methodology, integrating the developed criterion, the CZM to model the crack, a simple remeshing procedure to accommodate crack propagation, the J2 flow theory implemented within the incremental plasticity framework to model the ductile materials, and a local arc-length solver to the nonlinear equation system, is developed and implemented in an in-house program. Three examples, i.e., a plain concrete beam with a single shear crack, a reinforced concrete （RC） beam with multiple cracks and a compact-tension steel specimen, are simulated. Good agreement between numerical predictions and experimental data is found, which demonstrates the applicability of the criterion to both quasi-brittle and ductile materials.     

海带中碘含量的测定

将海带灰化后,用碘量法可测出其中的碘含量。测试表明,市售海带中,每克干海带碘含量为0.7~0.8mg。     

壳聚糖固定化As1.398中性蛋白酶稳定性的研究

研究了以中空球形壳聚糖固定As1 .398中性蛋白酶的方法 ,分析了戊二醛浓度、给酶量对固定化的影响 ,并对固定化酶的性质进行了讨论 ,实验结果显示 ,戊二醛质量浓度为 4 % ,每克载体给酶量 2 5mg时 ,酶活力回收为 65 .4% ,固定化酶的热稳定性、pH稳定性及乙醇的稳定性均高于游离酶     

金属氧化物/碳超级电容器复合材料研究进展

作为一种新型储能器件,超级电容器因其高能量密度、快速充放电、长循环寿命等特点得到了越来越多的关注.目前超级电容器电极材料的研究主要分为三类,即碳材料(C)、金属氧化物(MxOy)和导电聚合物(ECP),这三种材料各有优缺点.将两种或两种以上的电极材料进行组合制成复合材料,由于各组分间的协同效应可大幅度提高材料的整体电化学性能.其中MxOy/碳复合材料的研究较为广泛,该文综述了该类复合材料的分类和最新研究概况.     

The Effects of a Story-Reading Program on the Vocabulary and Story Comprehension Skills of Disadvantaged Prekindergarten and Kindergarten Students

This paper describes the development and effects of a story-reading program (STaR) on the language and comprehension of disadvantaged prekindergarten and kindergarten students. The story-reading program was developed as a part of a school restructuring effort, Success for All. STaR contains materials (sequence cards, flannel board materials), and methods (retelling, dramatization) to facilitate the effective use of stones in classrooms. Individual students from a matched control school were matched with experimental students in the pro- gram assessment. The Merrill Language Screening Test and the TOLD were individually administered to 206 prekindergarten (43 matched pairs) and kindergarten students (60 matched pairs) to measure program effects on language. Positive effects for program ranged from .24 to 3.75.     

乳化炸药用硝酸铵溶液原料系统设计

根据可直接使用硝酸铵溶液为原料的乳化炸药的生产工艺特点,研究建立了供直接使用的硝酸铵溶液原料技术标准,提出了适合运输、贮存热硝酸铵溶液的集装箱、贮存罐技术要求。直接使用硝酸铵溶液为原料生产乳化炸药可节能降耗,减少三废排放,是一种清洁生产的途径。     

野生猴头菌主要营养成分测定分析

测定了野生猴头菌子实体中粗蛋白,粗脂肪、微量元素、维生素及氨基酸等几种主要化学成分,测定结果表明野生猴头菌中蛋白含量高达5.67%,是目前最畅销食用菌蛋白含量的4倍;粗脂肪含量为3.14%,属于低脂肪菌类;微量无素含量均高于当今市场畅销菌;维生素含量丰富,其中维生素C每百克中舍698毫克,远高于一般食用菌.     

下一代存储技术--全息存储

本简要介绍了一种新的存储技术——全息存储，对当前正在研究的全息存储技术分别从原理、器件和记录材料等几个方面进行了相应介绍，同时给出了对全息存储系统的性能评价标准。     

乐山大佛基岩酸雨影响评价及防治对策

在酸雨的作用下,大佛砂岩的风化剥蚀作用很强烈,为定量研究酸雨对乐山大佛基岩的影响,实地采集了乐山大佛基岩及乐山酸雨样本,搜集了大量相关资料,进行了模拟酸雨试验。研究表明,乐山大佛早期的新鲜基岩,在长期的风化剥蚀作用下,由外到内形成了粉末层—硬壳层—风化层—新鲜基岩层,这一完整的表层层次结构。这种层次模式是由岩石表面逐渐递次向岩石内部发展的。通过模拟酸雨试验还发现,乐山大佛基岩,在最近30年酸雨的作用下,风化剥蚀作用强烈.,平均剥蚀速率在0.2克/小时·平方米左右,总计被剥蚀厚度约2厘米。提出了应更高度警惕酸雨对乐山大佛裸露基岩的破坏,进一步深化对乐山大佛裸露基岩保护的相应防治对策。     

过氧化钙的常温合成工艺研究

以氢氧化钙和过氧化氢为原料,通过添加稳定剂,实现了过氧化钙的常温合成,并考察了反应时间、加水量、稳定剂用量、氢氧化钙过量系数等因素对产品纯度和产量的影响,结果表明:在Ca(OH)2的用量为5 g,反应时间为5 min、加水量为10 mL、稳定剂用量为35 mg、氢氧化钙过量系数<5%时,产品中过氧化钙的含量可达到70%左右。     

From Jackfruit Rags to Hierarchical Porous N-Doped Carbon: A High-Performance Anode Material for Sodium-Ion Batteries

Renewable biomass-derived carbon materials have attracted increasing research attention as promising electrode materials for electrochemical energy storage devices, such as sodium-ion batteries(SIBs), due to their outstanding electrical conductivity, hierarchical porous structure, intrinsic heteroatom doping, and environmental friendliness. Here, we investigate the potential of hierarchical N-doped porous carbon(NPC) derived from jackfruit rags through a facile pyrolysis as an anode material for SIBs. The cycling performance of NPC at 1 A/g for 2000 cycles featured a stable reversible capacity of 122.3 mA·h/g with an outstanding capacity retention of 99.1%. These excellent electrochemical properties can be attributed to the unique structure of NPC; it features hierarchical porosity with abundant carbon edge defects and large specific surface areas. These results illuminate the potential application of jackfruit rags-derived porous carbon in SIBs.     

A Review on Applications of Layered Phosphorus in Energy Storage

Phosphorus in energy storage has received widespread attention in recent years. Both the high specific capacity and ion mobility of phosphorus may lead to a breakthrough in energy storage materials. Black phosphorus, an allotrope of phosphorus, has a sheet-like structure similar to graphite. In this review, we describe the structure and properties of black phosphorus and characteristics of the conductive electrode material, including theoretical calculation and analysis. The research progress in various ion batteries, including lithium-sulfur batteries, lithium–air batteries, and supercapacitors, is summarized according to the introduction of black phosphorus materials in different electrochemical applications. Among them, with the introduction of black phosphorus in lithium-ion batteries and sodium-ion batteries, the research on the properties of black phosphorus and carbon composite is introduced. Based on the summary, the future development trend and potential of black phosphorus materials in the field of electrochemistry are analyzed.     

丙硫氧嘧啶片的制备及处方优化

以丙硫氧嘧啶为研究对象,对其湿法制粒工艺处方进行优化。通过调节处方组成,对成片进行重量差异、含量测定、溶出度测定,硬度、脆碎度等片剂项目检查。经数据比较分析,对四个备选处方进行适用性研究,最终优选出最佳制片工艺处方为：丙硫氧嘧啶、淀粉、22.5%可压性淀粉浆及微晶纤维素的组分比为5∶2∶10∶2,每50 g丙硫氧嘧啶添加微粉硅胶2 g、硬脂酸镁1 g及十二烷基硫酸钠3 g,并可用于批量生产。     

基于工作过程的高职教材编写实践与思考--以高职《船舶建造》教材编写为例

结合《船舶建造》教材编写的成功案例,总结分析了基于工作过程编写教材的思考与实现过程,主要阐述了教材编写的一些经验：要有工作艰辛的思想准备,广而全的知识准备,充足的素材资料准备,同时要注重成果转化以及在教材编写中的注意事项等。这些都为编写高质量的教材方案提供了依据。     

基于powerpoint的CAI课件设计制作

powerpoint因其操作简单而备受教师青睐。用户设计CAI课件时借助其他专业软件可对图像、声音、视频等素材进行处理，并获得理想效果。本在分析素材制作方法的基础上，结合powerpoint的功能和技术特点，讨论了CAI课件的设计流程和注意事项，着重介绍节约存储空间的技巧。     

Intelligibility is equity: Can international students read undergraduate admissions materials?

Fewer international students have applied to and enrolled in US institutions, as 40 per cent of US institutions reported a drop in international applications since 2016. Subsequently, US institutions must ensure that their international admissions materials are as equitable and transparent as possible. Expanding previous work, this study examines the readability and translation of international undergraduate admissions materials of 335 four‐year public and non‐profit private US institutions. Results reveal these materials are written near a 14th‐grade reading comprehension level, only 1 per cent of institutions provide web‐embedded translation tools on their websites and 91 per cent of institutions provide English‐only content. Implications for practitioners, policymakers and future research are addressed.