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Effects of Slow-release Nitrogen Fertilizer on Yield and Nitrogen Accumulation of Summer Maize in Shajiang Black Soil Area

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Agricultural Biotechnology 2024年第2期13卷 72-74页

作者： Yongfeng XING Changmin WEI guoli chen Weimeng XU Wanyou SONG Guizhi LI Wenwei ZHOU Yanwei WAN Enzhong ZHOU Weifang LI Zhoukou Academy of Agricultural Sciences Zhoukou 466000China

[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the application scope and nitrogen metabolism mechanism, so as to lay a foundation for fertilizer reduction and efficiency improvement. [Methods] With maize variety Beiqing 340 and sulfur-coated urea as experimental materials, five nitrogen application levels were set, namely, control (C0), slow-release nitrogen 70 kg/hm^(2) (C70), slow-release nitrogen 140 kg/hm^(2) (C140), slow-release nitrogen 210 kg/hm^(2) (C210) and slow-release nitrogen 280 kg/hm^(2) (C280). The phosphorus and potassium fertilizers were all in accordance with the unified standard. [Results] With the application rate of slow-release nitrogen increasing, the nitrogen accumulation in organs increased first and then decreased after tasseling stage of maize. In order to reduce the fertilizing amount and increase efficiency, 210 kg/hm^(2) of slow-release nitrogen fertilizer was the best fertilizing amount for summer maize in Shajiang black soil area. [Conclusions] This study provides reference for fertilizer reduction, efficiency improvement and sustainable development of summer maize in Shajiang black soil area.

关键词： Slow-release nitrogen fertilizer Shajiang black soil Summer maize Nitrogen metabolism Yield

O-季铵盐氧化壳聚糖的合成及对棉织物的抗菌整理

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高等学校化学学报 2024年第3期45卷 143-155页

作者：周晓龙汪瑞琪陈国丽郭文明陈飞周炎孙立德汤大保许云辉安徽农业大学材料与化学学院合肥230036 安徽京九丝绸股份有限公司阜阳236000

通过香草醛与壳聚糖C2位氨基形成席夫碱以保护氨基,然后在C6位羟基上接枝2,3-环氧丙基三甲基氯化铵(GTA)季铵盐,利用稀HCl乙醇溶液脱除席夫碱后合成出O-季铵盐壳聚糖(O-HACC),再用KIO_(4)将O-HACC中C2和C3位的部分基团选择性地氧化为醛... 详细信息

通过香草醛与壳聚糖C2位氨基形成席夫碱以保护氨基,然后在C6位羟基上接枝2,3-环氧丙基三甲基氯化铵(GTA)季铵盐,利用稀HCl乙醇溶液脱除席夫碱后合成出O-季铵盐壳聚糖(O-HACC),再用KIO_(4)将O-HACC中C2和C3位的部分基团选择性地氧化为醛基,制备出能与纤维反应结合且具有双重抗菌活性的O-季铵盐氧化壳聚糖(O-HAOCC),随后接枝棉织物得到O-HAOCC改性棉织物.傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、氢核磁共振波谱(1H NMR)、扫描电子显微镜(SEM)和差示扫描量热分析(DSC)等结果表明,O-HAOCC分子中保留了氨基,同时引入了季铵盐结构和活性醛基,结晶形态被破坏,热稳定性降低.测试结果表明,氧化3h的O-HAOCC的水溶性高达237g/L,2,2′-联氮双(3-乙基苯并咪唑-6-磺酸)二铵盐(ABTS)自由基清除率在40 min后达到65.58%.当O-HAOCC质量分数为2%,反应时间为2 h,接枝温度为80℃时,改性棉织物的接枝率为9.84%.O-HAOCC改性棉织物对金黄色葡萄球菌和大肠杆菌的抗菌率分别为98.63%和93.38%,水洗50次后的抗菌率仍在90.75%以上,可应用于抗菌纺织服装、家纺面料和医疗卫生品等领域.

关键词：季铵盐壳聚糖香草醛选择性氧化结构性能抗菌织物

Molecular mechanism of the inhibitory effect of methylation outside the recognition sequence of restriction endonuclease Pvu Π on its cleavage activity

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Chinese Science Bulletin 1998年第1期43卷 47-52页

作者： chen Defeng, SUN Mei, LIU Yingmiao, SHI guoli and chen Yawen Institute of Molecular Biology, Nankai University, Tianjin 300071, China Institute of Molecular Biology Nankai University Tianjin China

In 1991, we found that methylation outside the PvuⅡ recognition sequence could partially inhibit its cleavage activity. To clarify the molecular mechanism, three plasmids with different methylation states were constructed. Then, together with the original one, four plasmids were digested with different amounts of PvuⅡ. Results show that methylation on both sites results in 90% inhibition; moving the methylated site one base further away decreases the inhibitory effect to about 30%; with the adjacent dam methylation site eliminated, the inhibitory effect disappears. The data suggest that the inhibition of cleavage activity caused by outside methylation is not "all or none", and the degree of inhibition is dependent on the position and the number of methylated bases.

关键词： methylation outside the recognition sequence molecular mechanism PCR sitespecific mutation restriction endonuclease PvuⅡ.

缓释氮肥对砂姜黑土区夏玉米产量及氮代谢的影响

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分子植物育种 2024年第11期22卷 3685-3695页

作者：邢永锋许卫猛魏常敏宋万友李桂芝周文伟万彦伟周恩忠李伟房徐超峰陈国立周口市农业科学院周口466000

为了明确砂姜黑土区夏玉米氮肥代谢及产量变化,探究缓释氮肥施用范围,本研究以玉米品种‘北青340’及硫包衣尿素为试验材料,设置不施氮肥(C0)、施缓释氮肥70 kg/hm^(2)(C70)、施缓释氮肥140 kg/hm^(2)(C140)、施缓释氮肥210 kg/hm^(2)(C... 详细信息

为了明确砂姜黑土区夏玉米氮肥代谢及产量变化,探究缓释氮肥施用范围,本研究以玉米品种‘北青340’及硫包衣尿素为试验材料,设置不施氮肥(C0)、施缓释氮肥70 kg/hm^(2)(C70)、施缓释氮肥140 kg/hm^(2)(C140)、施缓释氮肥210 kg/hm^(2)(C210)、施缓释氮肥280 kg/hm^(2)(C280)5个水平,磷钾肥均按统一标准施用。检测和分析缓释氮肥对砂姜黑土区夏玉米氮素吸收、积累、运转及同化的影响。结果显示,随缓释氮施用量的增加,玉米抽雄期以后,器官氮素吸收、积累、转运、同化量均呈先增后降低的趋势;器官氮素吸收、积累、转运、同化与产量的相关性有差异,与抽雄期-乳熟期氮素积累量、成熟期叶片氮素积累量呈负相关,其他正相关,同时器官氮素积累量及转运量与产量性状存在显著的线性相关关系。以减肥增效为标准,发现210 kg/hm^(2)的缓释氮肥是砂姜黑土区夏玉米较优的施肥量。本研究为砂姜黑土区夏玉米生产减肥增效提供参考。

关键词：缓释氮肥砂姜黑土夏玉米氮代谢产量

Single-cell transcriptomic analysis reveals transcript enrichment in oxidative phosphorylation,fluid sheer stress,and inflammatory pathways in obesity-related glomerulopathy

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Genes & Diseases 2024年第4期11卷 314-326页

作者： Yinyin chen Yushun Gong Jia Zou guoli Li Fan Zhang Yiya Yang Yumei Liang Wenni Dai Liyu He Hengcheng Lu Department of Nephrology Hunan Provincial People's HospitalThe First Affliated Hospital of Hunan Normal UniversityHunan Clinical Research Center for Chronic Kidney DiseaseChangshaHunan 410000China Department of Nephrology The Second Xiangya Hospital of Central South UniversityHunan Key Laboratory of Kidney Disease and Blood PurificationChangshaHunan 410011China Cardiovascular Research Institute of Jiangxi Province Jiangxi Provincial People's HospitalThe First Affiliated Hospital of Nanchang Medical CollegeNanchangJiangxi 330006China

Obesity-related glomerulopathy(ORG)is an independent risk factor for chronic kid-ney disease and even progression to end-stage renal *** have been undertaken to elucidate the mechanisms underlying the development of ORG and substantial advances have been made in the treatment of ORG,but relatively little is known about cell-specific changes in gene *** define the transcriptomic landscape at single-cell resolution,we analyzed kidney samples from four patients with ORG and three obese control subjects without kidney disease using single-cell RNA *** report for the first time that immune cells,including T cells and B cells,are decreased in ORG *** analysis indicated that SPP1 was significantly up-regulated in T cells and B *** gene is related to inflammation and cell *** of differential gene expression in glomerular cells(endothelial cells,mesangial cells,and podocytes)showed that these cell types were mainly enriched in genes related to oxidative phosphorylation,cell adhesion,thermogenesis,and inflammatory pathways(PI3K-Akt signaling,MAPK signaling).Furthermore,we found that the podocytes of ORG patients were enriched in genes related to the fluid shear stress ***,an evaluation of cell-cell communications revealed that there were interactions between glomerular parietal epithelial cells and other cells in ORG patients,with major interactions between parietal epithelial cells and ***,our identification of molecular events,cell types,and differentially expressed genes may facilitate the development of new preventive or therapeutic approaches for ORG.

关键词： Fluid shear stress Inflammation Obesity-related glomerulopathy Oxidative phosphorylation Single-cell RNA seq

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从PHS在日本的兴衰看其应用定位

电信科学 1999年第5期15卷 29-32页

作者：陈国利邮电部设计院

本文简述了ＰＨＳ在日本的兴衰史，从运营、技术、历史等方面分析了ＰＨＳ在我国用作“移动市话”的不切实际性。ＰＨＳ的技术特点表明其最佳应用定位可能是无线ＰＡＢＸ。

关键词：移动市话 PHS WPABX 日本应用定位

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试论渔业环境保护中渔政渔监机构的法律地位

中国水产 2000年第4期293卷 14-15页

作者：陈国生中国渔政福州船队

当前,随着我国环境保护法律、法规的进一步健全与完善,以及《行政诉讼法》、《国家赔偿法》、《行政处罚法》等一系列法律、法规的颁布与实施,给渔政渔港监督管理机构的执法提出了新的更高的要求.

关键词：中国渔业环境保护渔政渔港监督管理机构

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二氧化碳驱开发效果评价方法

大庆石油地质与开发 2016年第1期35卷 92-96页

作者：陈国利中国石油吉林油田公司勘探开发研究院吉林松原138000

为促进CO_2驱油与埋存技术的发展,需要建立一套系统全面的CO_2驱开发效果评价方法和指标。针对CO_2驱开发特点,按照系统、规范、实用的原则,考虑评价的多角度多层次,建立了CO_2驱开发效果评价方法及指标体系,确定了技术效果、经济效益... 详细信息

为促进CO_2驱油与埋存技术的发展,需要建立一套系统全面的CO_2驱开发效果评价方法和指标。针对CO_2驱开发特点,按照系统、规范、实用的原则,考虑评价的多角度多层次,建立了CO_2驱开发效果评价方法及指标体系,确定了技术效果、经济效益和安全环保等3个方面15项评价指标。通过在某油田CO_2驱试验区应用表明:该评价方法及指标符合CO_2驱开发实际,重点突出,系统全面,规范实用。

关键词： CO2驱评价方法指标技术效果经济效益安全环保

纳米TiO_2/聚丙烯腈抗紫外线吸收剂的合成及性能

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高分子材料科学与工程 2018年第1期34卷 31-35,40页

作者：陈国力王雅珍王文波殷广明齐齐哈尔大学化学与化学工程学院分析测试中心齐齐哈尔大学材料科学与工程学院黑龙江齐齐哈尔161006

在乙醇和水介质中通过调节pH值对纳米TiO_2进行γ-甲基丙烯酰氧基丙基三甲氧基硅烷(MPS)包覆,在溶液中包覆物TiO_2-MPS和丙烯腈(AN)在引发剂的作用下发生共聚和接枝反应,制备出紫外吸收剂TiO_2-MPS-g-PAN。通过傅里叶变换红外光谱和X射... 详细信息

在乙醇和水介质中通过调节pH值对纳米TiO_2进行γ-甲基丙烯酰氧基丙基三甲氧基硅烷(MPS)包覆,在溶液中包覆物TiO_2-MPS和丙烯腈(AN)在引发剂的作用下发生共聚和接枝反应,制备出紫外吸收剂TiO_2-MPS-g-PAN。通过傅里叶变换红外光谱和X射线光电子能谱对MPS、TiO_2-MPS、TiO_2-MPS-g-PAN进行了比较分析;采用热重分析法测定TiO_2-MPS的包覆率为5.79%,TiO_2-MPS-g-PAN的接枝率为13.93%;通过红外成像分析了TiO_2、TiO_2-MPS、TiO_2-MPS-g-PAN在聚丙烯(PP)中的分散性,结果表明TiO_2-MPS-g-PAN在PP中有较好的分散性;通过紫外分光光度计测试计算出TiO_2-MPS-g-PAN的光降解率仅为2.66%,表明具有较好的光稳定性和紫外吸收能力。

关键词：紫外添加剂分散性抗紫外线能力