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Advances and Prospects in Breeding Japonica Rice for Super High Yield inthe Northern China

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Agricultural Sciences in China 2007年第10期6卷 1157-1165页

作者： chen wen-fu xu Zheng-jin ZHANG wen-zhong Rice Research Institute Shenyang Agricultural University Shenyang 110161 P.R.China

In this paper, advances and prospects in breeding japonica rice for super high yield in the northern China were analyzed comprehensively in terms of breeding theories, techniques and practices. The author holds that developing and spreading super rice is an important way to enhance the overall yielding ability of japonica rice and attaining immense expansion of rice production. After theories and technical guidelines for super rice breeding were formulated, which involved the creation of new plant morphology and strong hybrid vigor through crossing indica with japonica subspecies, the optimization of combination of desirable traits via multiple crossing or backcrossing, the assemblage of favorable genes and the integration of ideal plant morphology with the utilization of vigor-major breakthroughs have been made in conventional breeding of japonica super rice. A batch of new super rice varieties marked by superior rice quality and high disease resistance, such as Shennong 265, Shennong 606, and Jijing 88, etc., have been developed and released. In comparison with the advancement in conventional breeding ef super rice, progress in hybrid japonica super rice breeding is slower because of climatic and ecological constraint in northern China. Therefore, solving the contradictions between vigor and growth duration, between yield and rice quality, and boosting vastly seed production are still serious challenges for breeders of hybrid japonica rice. Physiological and genetic problems in japonica super rice breeding are also discussed in this paper.

关键词： rice ideal plant morphology japonica super rice

Growth and Contaminant Removal Effect of Several Plants in Constructed Wetlands

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Journal of Integrative Plant Biology 2009年第3期51卷 325-335页

作者： Xiu-Yun cheng Ming-Qiu Liang wen-Yin chen xu-cheng Liu Zhang-He chen Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education and Guangdong Provincial Key Laboratory of Biotechnology for Plant Development College of Life Science South China Normal University Guangzhou 510631 China

The aim of the present study is to probe the relation between plant growth and its decontamination effect in constructed wetlands. Four species were studied in the small-scale mono-cultured constructed wetlands, which were fed with domestic wastewater. Plant growth indexes were correlated with contaminant removal performance of the constructed wetlands. Wetlands planted with Cyperus flabelliformis Rottb. showed the highest growth indexes such as shoot growth, biomass, root activity, root biomass increment, and the highest contaminant removal rates, whereas wetlands planted with Vetiveria zizanioides L. Nash had the lowest growth indexes and the lowest removal rates. Above-ground biomass and total biomass were significantly correlated with ammonia nitrogen removal, and below-ground biomass with soluble reactive phosphorus removal. Photosynthetic rate had higher correlation with nitrogen removal in these species. Root activity and root biomass increment was more correlated with 5 d biochemical oxygen demand removal. Chemical oxygen demand removal had lower correlations with plant growth indexes. All four species had higher removal rates in summer and autumn. The results suggest that the effect of plant growth on contaminant removal in constructed wetlands were different specifically in plants and contaminants.

关键词： constructed wetland contaminant removal growth plant.

STUDY OF COMPOSITE BY MELTING INTERCALATION OF POLYACRYLAMIDE IN MONTMORILLONITE

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Journal of Wuhan University of Technology(Materials Science) 1998年第2期13卷 32-36页

作者：陈文 Wuhan University of Technology China Coll. of Mat. Sci. and Engineering Wuhan Univ. of Tech. Wuhan 430070 China

The synthesis of polyacrylamide (PAM)-montmorillinote composite by direct melting intercalation of polymer powders is studied using XRD, IR and DSC. The results show that melt PAM can intercalate into montmorillonite layer. The layered distance(d//0//0//1) of montmorillonite increases, and the melt absorption peak of PAM in layer has eliminated. (Author abstract) 8 Refs.

关键词： PAM melt intercalation montmorillonite intercalation composite

PSD95 Gene Specific siRNAs Attenuate Neuropathic Pain through Modulating Neuron Sensibility and Postsynaptic CaMKIIα Phosphorylation

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Chinese Medical Sciences Journal 2011年第4期26卷 201-207页

作者： Le Shen xu Li wen chen Li xu Wei Liu xue-rong Yu Yu-guang Huang Department of Anesthesiology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China

Objective To observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo. Methods Gene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: nave group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively. Results The siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated. Conclusion Pre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.

关键词： PSD95 siRNAs neuropathic pain glutamate excitotoxicity calcium/calmodulin- dependent protein kinase IItt

Influence of Mo content on microstructure and mechanical properties of β-containing TiAl alloy

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Transactions of Nonferrous Metals Society of China 2017年第4期27卷 820-828页

作者： wen-chen xu Kai HUANG Shi-feng WU Ying-ying ZONG De-bin SHAN School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China

The influence of Mo content on the microstructure and mechanical properties of the Ti?45Al?5Nb?xMo?0.3Y(x=0.6,0.8,1.0,1.2)alloys was studied using small ingots produced by non-consumable electrode argon arc *** results show that smallquantities ofβphase are distributed alongγ/α2lamellar colony boundaries as discontinuous network in the TiAl alloys owing to thesegregation of Mo ***γphase forms in the interdentritic microsegregation area when the Mo addition exceeds0.8%.Theβandγphases can be eliminated effectively by subsequent homogenization heat treatment at the temperature above Tα.The evolutionof the strength,microhardness and ductility at different Mo contents under as-cast and as-homogenization treated conditions wasanalyzed,indicating that excessive Mo addition is prone to cause the microsegregation,thus decreasing the strength andmicrohardness obviously,which can be improved effectively by subsequent homogenization heat treatment.

关键词： TiAl alloy β phase microstructure mechanical properties homogenization treatment

基于IEC 61850的集中式馈线自动化信息模型

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电力系统自动化 2017年第8期41卷 133-137页

作者：王志熊文陈羽徐丙垠山东理工大学电气与电子工程学院山东省淄博市255049 广州供电局有限公司广东省广州市510620

配电系统中广泛应用的集中式馈线自动化为满足配电主站与配电终端间互联互通,对构建符合IEC 61850标准的信息模型提出了迫切需求。介绍了IEC 61850-90-6技术报告中故障指示相关逻辑节点,在分析集中式馈线自动化工作原理的基础上,基于新... 详细信息

配电系统中广泛应用的集中式馈线自动化为满足配电主站与配电终端间互联互通,对构建符合IEC 61850标准的信息模型提出了迫切需求。介绍了IEC 61850-90-6技术报告中故障指示相关逻辑节点,在分析集中式馈线自动化工作原理的基础上,基于新定义的电流指示逻辑节点SCPI、电压指示逻辑节点SVPI、故障指示逻辑节点SFPI,研究了集中式馈线自动化功能实现的信息模型,推动了IEC 61850标准在配电自动化中的应用。

关键词：配电自动化馈线自动化集中控制 IEC 61850

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21世纪全球公共危机治理新挑战及中国智慧

湖南大学学报（社会科学版） 2021年第6期35卷 7-14页

作者：陈文旭北京大学马克思主义学院北京100871

进入21世纪,全球公共危机呈现出传统和非传统安全扭结相缠、风险全球化程度加剧、信息技术影响凸显、次生危机复杂性加剧等一系列新特征。现行全球公共危机治理体系面临着诸多挑战,特别是资本的扩张本性导致全球公共危机治理实践忽视生... 详细信息

进入21世纪,全球公共危机呈现出传统和非传统安全扭结相缠、风险全球化程度加剧、信息技术影响凸显、次生危机复杂性加剧等一系列新特征。现行全球公共危机治理体系面临着诸多挑战,特别是资本的扩张本性导致全球公共危机治理实践忽视生产力发展实际并违背世界历史运行总体规律。世界各国应顺应历史发展大势,以全人类共同利益为基本出发点,在推进全球公共危机治理进程中,努力构建全球公共危机治理共同体。作为世界负责任的大国,中国同世界各国一道积极应对全球公共危机治理新挑战,推动全球公共危机治理共同体的建构,为实现有效全球治理贡献中国智慧、提供中国方案。

关键词：全球公共危机全球治理人类命运共同体中国智慧

马克思主义视域下的“时代新人”学术研究述评

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中国青年社会科学 2020年第6期39卷 60-67页

作者：陈文旭北京大学马克思主义学院北京100871

自党的十九大习近平总书记正式提出“培养担当民族复兴大任的时代新人”以来,马克思主义学界对“时代新人”的研究逐步深入。内涵研究主要包括“二重”内涵说、“理想人格”要素说和多维属性说;特征研究可分为“一元论”和“多元论”;... 详细信息

自党的十九大习近平总书记正式提出“培养担当民族复兴大任的时代新人”以来,马克思主义学界对“时代新人”的研究逐步深入。内涵研究主要包括“二重”内涵说、“理想人格”要素说和多维属性说;特征研究可分为“一元论”和“多元论”;认为“时代新人”的生成有其历史发展逻辑,也具备现实基础和实现可能性。未来“时代新人”的学术研究需要采取跨学科、多视角的方式深化对“时代新人”的内涵认识,进一步构建“时代新人”的理论研究框架,加强关于“时代新人”的实证调查研究,拓展“时代新人”研究视域,构建“时代新人”话语体系。

关键词：马克思主义时代新人话语体系

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基于FRM的偶型排列信道化改进结构

北京邮电大学学报 2016年第3期39卷 27-33页

作者：张文旭陈亚静陈涛窦峥哈尔滨工程大学信息与通信工程学院哈尔滨150001

针对窄过渡带信道化设计带来的复杂度较高问题,提出了一种基于频率响应屏蔽(FRM)的偶型排列信道化改进结构.结构中的原型滤波器设计采用半带滤波器,两个屏蔽滤波器由同一个低通滤波器调制得到,然后合成上下支路的输出信号,得到各个通道... 详细信息

针对窄过渡带信道化设计带来的复杂度较高问题,提出了一种基于频率响应屏蔽(FRM)的偶型排列信道化改进结构.结构中的原型滤波器设计采用半带滤波器,两个屏蔽滤波器由同一个低通滤波器调制得到,然后合成上下支路的输出信号,得到各个通道的子带信号.推导得到的非最大抽取FRM改进结构相比传统的滤波器组结构具有较小的计算复杂度,同时将抽取模块置于最前端信道化处理,不受采样率较高的限制,具有较为广泛的适用性.在信道数为16的条件下,计算机仿真结果验证了结构设计的正确性,相比多相结构可节省67.9%的乘法器资源.

关键词：频率响应屏蔽原型滤波器偶型排列屏蔽滤波器非最大抽取