Results 1 to 10 of about 1,121,913 (165)
Zhejiang Daxue xuebao. Lixue ban, 2008 在鼓泡碳化法制备的普通及纳米碳酸钙表面包覆上一层羟基氧化铝，根据差热热重分析实验数据，采用master-plot标准作图法和经典动力学机理方程确定了碳酸钙的分解机理并求取相应动力学参数.普通碳酸钙包覆后分解机理由R2变为D1，纳米碳酸钙包覆后分解机理由R3变为R2.用微分和积分方法验证活化能得到很好的一一对应结果.对包覆二元复合物特殊的热分解动力学行为做了初步解释.
ZHANGHui-zhu(张惠珠) +2 more
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Gongye shui chuli, 2021 分别以香蕉秸秆（BS）、木薯秸秆（CS）为原料，采用限氧热解法在不同热解温度下制备生物炭，采用元素分析、Boehm滴定、BET、FTIR、XRD等方法分析了生物炭的基本特性，研究了生物炭对Cd2+的吸附特性和作用机制。结果表明，热解温度能显著影响生物炭的产率、灰分、pH、孔径结构以及元素分布等性质；生物炭吸附过程符合准二级动力学；生物炭对Cd2+的吸附作用机制主要表现为络合作用和沉淀作用，K+、Na+、Mg2+、Ca2+共存会影响Cd2+的吸附，且热解温度越低，影响作用越大。
康彩艳 +5 more
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Diversity of culturable thermophiles from hotsprings of Mid-China(我国中部地区热泉嗜热菌的分离及其产酶研究)
Zhejiang Daxue xuebao. Lixue ban, 2008 从我国中部的四川喜德、普格地区以及陕西南部地区分别采集地表热泉和地下热水水样，采用培养方法分离得到47株中度嗜热细菌.16S rRNA基因片段序列的分析和比对结果表明，采集地的嗜热细菌以芽孢杆菌为主，并且主要分布在Anoxybacillus和Geobacillus 2个属中.同时，通过平板法对分离的嗜热菌进行产酶定性实验，发现其在60 ℃或70 ℃条件下能够分泌多种耐热的水解酶类，其中60%的菌株能够利用吐温，38%的菌株分泌蛋白酶，29%的菌株能够降解木聚糖，38%的菌株产生淀粉酶.根据筛酶统计结果 ...
LIYang-xia(李杨霞) +4 more
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Gaoya dianqi, 2020 文中为了研究气压对SF6热分解反应的作用机制,构建了SF6分解气室的多物理场仿真模型,计算了不同气压下SF6分解气室内部的温度场和流体场分布;在微观角度上基于碰撞理论推导得到了气压对SF6过热分解反应的影响特性;并结合不同气压下SF6局部过热分解实验数据,阐释了气压对SF6热分解反应的作用机制。研究结果表明:随着SF6气压的升高,热源附近高温区域的体积增大,同时等温域内SF6与H2O和O2分子有效碰撞次数增加,在双重促进作用下致使SF6过热分解速率明显加快 ...
赵天成 +4 more
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Zhejiang Daxue xuebao. Lixue ban, 2007 采用两亲嵌段共聚物聚丙烯酸-苯乙烯(PS-b-PAA)水溶液为介质合成了球形碳酸钙复合物，球形直径约3~4 µm，由纳米级方解石微粒通过PS-b-PAA的有机键合紧密团聚而成.通过电镜、XRD、IR和差热热重分析复合物的微晶结构性质表明，复合物中有机质质量分数约为14%；其中的方解石微晶约几十纳米，较之普通碳酸钙晶体有更大的晶格畸变；热分解行为提前约15 ℃，红外v3吸收蓝移约10 cm-1.
JINYi-ping(金一平) +2 more
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International Journal of Applied Linguistics, EarlyView.ABSTRACT This study conducted linguistic analyses of the written corrective feedback (WCF) for Chinese as a second language (CSL) provided by chat generative pre‐trained transformer (ChatGPT) and human teachers (including preservice teachers and senior teachers).
Ling Zhang +2 more
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International Journal of Applied Linguistics, EarlyView.ABSTRACT In this study, control–value theory (CVT) was used to investigate how students’ perceptions of the classroom environment shape their anxiety in the context of English as a foreign language (EFL) learning through the mediating effects of control and intrinsic value appraisals.
Quan Qian, Xianhan Huang
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT The construction of core–shell grains can enhance the coercivity of Nd2Fe14B magnets. However, it is a significant challenge to elucidate the formation of these core–shell grains particularly regarding the spontaneous core–shell structure in Y‐substituted Nd2Fe14B alloys.
Sining Fan +13 more
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Biodegradable Zn‐based alloys are promising candidates for temporary implants, yet excessive Zn2+ release during degradation may induce cytotoxicity and adverse tissue responses. In this study, Zn‐xBa alloys (x = 0.1 wt%, 0.5 wt%, 1.0 wt% and 3.0 wt%) were developed to achieve controlled corrosion behaviors with improved biocompatibility.
Liu‐Dang Fang +9 more
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Direct solver for a difference approximation of the Forward-backward(Forward-backward热方程差分逼近的直接算法)
Zhejiang Daxue xuebao. Lixue ban, 2002 通过利用区域分解技术和并行算法的思想,把原问题分解为几个完全独立的子区域上的问题,并直接并行求解,然后把这些解作适当的线性组合,得到原问题的解.给出了Forward-backward热方程的差分逼近的直接算法.
YEXing-de(叶兴德)
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