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低温贮藏对南丰蜜桔中橘小实蝇的致死作用及其对南丰蜜桔糖酸含量的影响

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应用昆虫学报 2024年第2期61卷 322-329页

作者：吴家展王广利汪涛路天王建国李伟军李小珍江西农业大学农学院

【目的】柑橘重大害虫橘小实蝇Bactrocera dorsalis (Hendel)已经传入江西南丰蜜桔产区，影响南丰蜜桔的生产、贮藏和出口。研究低温对南丰蜜桔果实中橘小实蝇卵和幼虫的致死作用，及其对南丰蜜桔果实糖/酸含量的影响，有利于发展南丰... 详细信息

【目的】柑橘重大害虫橘小实蝇Bactrocera dorsalis (Hendel)已经传入江西南丰蜜桔产区，影响南丰蜜桔的生产、贮藏和出口。研究低温对南丰蜜桔果实中橘小实蝇卵和幼虫的致死作用，及其对南丰蜜桔果实糖/酸含量的影响，有利于发展南丰蜜桔鲜果的低温贮藏技术，为南丰蜜桔鲜果的安全出口提供信息。【方法】将接入橘小实蝇卵和幼虫的南丰蜜桔和健康的南丰蜜桔成熟果实，分别放置在温度为3和5℃的冷库，测定不同贮藏时间下橘小实蝇卵和幼虫的死亡率以及南丰蜜桔果实内可溶性糖和可滴定酸的含量。【结果】南丰蜜桔中橘小实蝇2-3龄幼虫对低温3和5℃的耐受力强。低温条件下，延长南丰蜜桔贮藏时间，果实内部橘小实蝇卵和幼虫的死亡率提高。低温3℃条件下，南丰蜜桔果实内部50%橘小实蝇卵和幼虫死亡的处理时间为2.37-3.15 d，全部个体死亡的处理时间为11 d;5℃条件下，50%个体死亡的处理时间为3.07-3.87d，全部个体死亡的时间为13d。健康南丰蜜桔鲜果在低温3和5℃条件下，延长贮藏时间，失重率和可溶性糖含量提高，可滴定酸含量下降。低温3和5℃贮藏13d，南丰蜜桔果实表面无冻伤；可溶性糖含量较高，分别达到16.65%和17.03%；可滴定酸含量低，分别为1.18%和1.16%。【结论】南丰蜜桔在低温3和5℃条件下贮藏13 d，既能彻底杀灭果实内部橘小实蝇卵和幼虫，又能较好保持南丰蜜桔成熟果实品质，是南丰蜜桔的理想贮藏条件。

关键词：橘小实蝇低温处理南丰蜜桔果实品质贮藏时间

Geographical Information System-Based Assessment of Ecological Security in Changbai Mountain Region

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Journal of Mountain Science 2014年第1期11卷 86-97页

作者： LU Xing-chang ZHANG Ji-quan li xiao-zhen School of Environment Northeast Normal University College of Geo-exploration Science & Technology Jilin University Anyang City Bureau of Agriculture

Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social *** recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological *** on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was *** results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.

关键词： Ecological security Pressure-State-Impact-Response Land use and cover change Geographical Information System(GIS) Catastrophe progression Changbai Mountain

Two new glycosides from the seeds of Cassia obtusifolia

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Chinese Chemical Letters 2009年第9期20卷 1097-1099页

作者： Cun Zhang Gui liu li Yong Qing xiao li li zhen Pang Institute of Traditional Chinese Materia Madica Chinese Academy of Chinese Medical Sciences Beijing 100700 China

Two new glycosides, nor-rubrofusadn-6-O-β-D-（6＇-O-acetyl）glucopyranoside （1） and 1-desmethylaurantio-obtusin-2-O-β-D- glucopyranoside （2） were isolated from the seeds of Cassia obtusifolia and their structures were established by chemical and spectral evidences. 2009 Yong Qing xiao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cassia obtusifolia Nor-rubrofusarin-6-O-β-D-(6'-O-acetyl)glucopyranoside 1-Desmethylaurantio-obtusin-2-O-β-D-glucopyranoside

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配合饲料混合均匀度3种测定方法的比较分析

饲料研究 2024年第7期47卷 110-115页

作者：唐连英李晓珍吴志艳郑永凤王迪李琦华鲁琼芬云南农业大学动物科学技术学院云南昆明650201 云南西南农牧集团股份有限公司云南昆明650224 云南省动物营养与饲料重点实验室云南昆明650201

试验旨在对3种(甲基紫法、摩尔法、氯离子选择电极法)测定饲料混合均匀度的方法进行分析比较,为饲料企业选择测定方法提供参考。试验选用仔猪前期配合饲料、乳猪浓缩饲料、中猪配合饲料、肉鸡前期料、肉鸡中期料和肉鸡后期料6种饲料,每... 详细信息

试验旨在对3种(甲基紫法、摩尔法、氯离子选择电极法)测定饲料混合均匀度的方法进行分析比较,为饲料企业选择测定方法提供参考。试验选用仔猪前期配合饲料、乳猪浓缩饲料、中猪配合饲料、肉鸡前期料、肉鸡中期料和肉鸡后期料6种饲料,每种饲料采集两个批次,共计120个样本,采用甲基紫法、摩尔法、氯离子选择电极法测定饲料的混合均匀度。结果显示:氯离子选择电极法测定的6种饲料混合均匀度变异系数(CV)均在国家标准允许范围10.00%以下,甲基紫法测定结果除中猪配合饲料以外,其余5种饲料均小于10.00%;摩尔法测定的3种猪饲料的混合均匀度均小于10.00%,3种鸡饲料混合均匀度均大于10.00%。用甲基紫法测定的中猪配合饲料的混合均匀度变异系数显著大于氯离子选择电极法(P<0.05);用摩尔法测定的肉鸡前期料和中期料混合均匀度的变异系数均显著大于甲基紫法和氯离子选择电极法(P<0.05);用摩尔法测定肉鸡后期料混合均匀度的变异系数显著大于甲基紫法和氯离子选择电极法(P<0.05),甲基紫法测定肉鸡后期料混合均匀度显著大于氯离子选择电极法(P<0.05)。研究表明,使用氯离子选择电极法测定6种饲料混合均匀度的效果较好。

关键词：饲料混合均匀度甲基紫法摩尔法氯离子选择电极法

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Dehalogenation of Aryl Halides Catalyzed by MontK10 Immobilized PVP-Pd-Sn Catalyst in Aqueous System

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Chinese Chemical Letters 2001年第4期12卷 287-290页

作者： xiao li zhen Jian Rong HAN Ru Hong KANG Xing Mei OUYANG Department of Essential Education Hebei Science(Technique UniversityShijiazhuang 050018 Department of Chemistry Heibei Normal UniversityShijiazhuang 050016

A series of PVP-Pd-Sn/MontK10 catalysts were prepared by immobilization of PVP[poly(N-vinyl-2-pyrrolidone)] supported bimetallic catalyst using MontK10 as carrier. This catalyst has good catalytic activity for hydrogen transfer dehalogenation of aryl halides. The catalytic reaction was carried out in aqueous system in the presence of phase transfer catalyst and sodium formate as hydrogen source. The catalyst with loading Pd 0.19wt% and molar ratio of Pd/Dn 8:1 gives the highest activity and good stability. This catalyst is more reducible with NaBH4. It is also found that the catalyst is easily separated from the reaction system.

关键词： Phase transfer catalyst aryl halide dehalogenation MontK10

MiR-301a promotes embryonic stem cell differentiation to cardiomyocytes

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World Journal of Stem Cells 2019年第12期11卷 1130-1141页

作者： li-xiao zhen Yu-Ying Gu Qian Zhao Hui-Fang Zhu Jin-Hui Lv Shu-Jun li zhen Xu li li Zuo-Ren Yu Key Laboratory of Arrhythmias of the Ministry of Education of China Tongji University School of MedicineShanghai 200120China Research Center for Translational Medicine Shanghai East HospitalTongji University School of MedicineShanghai 200120China Department of Microbiology and Immunology Wenzhou Medical CollegeWenzhou 325000Zhejiang ProvinceChina

BACKGROUND Cardiovascular disease is the leading cause of death *** repair after pathological injury in the heart remains a major challenge due to the limited regenerative ability of cardiomyocytes in *** cell-derived cardiomyocytes provide a promising source for the cell transplantation-based treatment of injured *** To explore the function and mechanisms of miR-301a in regulating cardiomyocyte differentiation of mouse embryonic stem(mES)cells,and provide experimental evidence for applying miR-301a to the cardiomyocyte differentiation induction from stem *** mES cells with or without overexpression of miR-301a were applied for all functional *** hanging drop technique was applied to form embryoid bodies from mES *** markers including GATA-4,TBX5,MEF2C,andα-actinin were used to determine cardiomyocyte differentiation from mES *** High expression of miR-301a was detected in the heart from late embryonic to neonatal *** of miR-301a in mES cells significantly induced the expression of cardiac transcription factors,thereby promoting cardiomyocyte differentiation and beating cardiomyocyte clone *** is a target gene of miR-301a in ***-regulated PI3K-AKT-mTOR-Stat3 signaling showed involvement in regulating miR-301a-promoted cardiomyocyte differentiation from mES *** MiR-301a is capable of promoting embryonic stem cell differentiation to cardiomyocytes.

关键词： miR-301a Mouse embryonic stem cells Differentiation Cardiomyocytes

A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network

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China Communications 2024年第2期21卷 122-128页

作者： xiao li ling Zhao zhen Dai Yonggang Lei School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Beijing Institute of Tracking and Telecommunications Technology BITTT

This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1dB improvement compared to Fully Convolutional Networks(FCN).

关键词： belief propagation channel decoding correlated noise neural network

一种基于低温共烧陶瓷技术的一分二功率分配器设计方法

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化工自动化及仪表 2024年第2期51卷 192-198,364页

作者：胡雨婷侯明李小珍徐开心张杨昆明理工大学信息工程与自动化学院昆明学院信息工程学院

从小型化的要求出发,提出一种一分二等分功率分配器设计方法。以Wilkinson功率分配器结构为基础,将传统功率分配器中的直线型传输线改为螺旋线型传输线。采用低温共烧陶瓷(LTCC)技术进行小型化功率分配器设计,建模时利用立体叠层结构对... 详细信息

从小型化的要求出发,提出一种一分二等分功率分配器设计方法。以Wilkinson功率分配器结构为基础,将传统功率分配器中的直线型传输线改为螺旋线型传输线。采用低温共烧陶瓷(LTCC)技术进行小型化功率分配器设计,建模时利用立体叠层结构对功率分配器内部的传输线进行布局,内部不同金属层之间使用垂直通孔连接,使得该功率分配器尺寸与传统平面结构功率分配器相比大幅减小。在HFSS软件中完成三维模型建立与电磁仿真,并对设计完成的功率分配器进行加工测试,最终得到该功率分配器回波损耗优于19 dB,插入损耗优于3.5 dB,中心频率2.8 GHz处隔离度优于35 dB,具有较好的隔离度,满足一分二等分功率分配器的性能要求,并且LTCC功率分配器尺寸仅3.18 mm×1.58 mm×0.911 mm。

关键词：一分二等分功率分配器 LTCC 螺旋线结构回波损耗插入损耗中心频率隔离度

Total Synthesis of N-Methylsansalvamide A

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Chinese Chemical Letters 2006年第6期17卷 761-764页

作者： Shou Xin liU Yan Lou GENG Xia TIAN xiao li zhen Jian Rong HAN College of chemical ＆ pharmaceutical Engineering Hebei University of Science ＆ Tecnnology Shijiazhuang 050018

Total synthesis of N-methylsansalvamide A was accomplished in solution phase by a convergent approach. An N-Boc-td-depsipepide 6 and a dipeptide ester 10 were prepared in the yield of 89% and 91%, respectively. Cycliz... 详细信息

关键词： Synthesis N-methylsansalvamide A solution phase cyclic depsipeptide.