检索结果-南通市图书馆

Commercial genetically modified corn and soybean are poised following pilot planting in China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2024年第4期17卷 519-521页

作者： Mei Sun Suzhen Li Wenzhu Yang Bowen Zhao Youhua Wang xiaoqing liu Biotechnology Research Institute Chinese Academy of Agricultural ScienceBeijing 100081China Farmers'Daily Beijing 100025China

"Who will feed China?"This was a question raised by Lester Brown,the director of the World Watch Institute in the United States,in 1994.He predicted that China's grain production would decrease from 340 million tons in 1990 to 272 million tons by 2030,a 20%decrease,while China's population would reach 1.6 billion(Brown,1995).If the dietary structure was not improved,China would need to import 200-369 million tons of grain,equivalent to the global grain trade at the time.He projected the high possibility of a food crisis in China,which might further trigger a global food crisis.However,with the joint efforts of national agricultural researchers,represented by Yuan Longping,and the Chinese government,China's grain production has achieved 18 consecutive increases from 2004 to 2021.In 2022,grain production in China reached 633 million tons(NBS and Statistics,2022),while the population remained stable at 1.4 billion.As a result,China has achieved complete self-sufficiency in its staple food supply and has demonstrated to the international community through practical actions that the Chinese people can feed themselves.

关键词： planting soybean raised

Surface engineering of carbon dots for highly sensitive α-glucosidase assay and inhibition evaluation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第3期35卷 193-197页

作者： Meijuan Liang Gege Song Yeqing Wan Yingying Chen Fuan Wang xiaoqing liu College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China Oil Crops Research Institute Chinese Academy of Agricultural SciencesWuhan 430062China

Monitoringα-glucosidase(α-Glu)activity is of great significance for the early diagnosis of typeⅡdiabetes.Here the blue fluorescent carbon dots(CDs)were integrated with two different recognizing molecules,β-cyclodextrin and phenylboronic acid,for assembling a multifunctional CDs(mCDs)nanoplatform for sensitively analyzingα-Glu and its inhibitors.The hydrolyzed product of 4-nitrophenyl-α-D-glucopyranoside(α-Glu substrate),p-nitrophenol,could efficiently quench the fluorescence of mCDs due to its cooperative molecular recognition withβ-cyclodextrin and phenylboronic acid.The mCDs could be utilized for the detection ofα-Glu activity with the limit of detection of 0.030 U/L.Moreover,the presentα-Glu detection platform revealed a high selectivity,and other natural enzymes showed scarcely any effect on the present mCDs system.The proposed method could be facilely used to screenα-Glu inhibitors with satisfying performance.The rational mCDs is expected to supplement more comprehensive biosensing platforms for highly sensitive and specific recognition of disease-relevant biomarkers with clinical importance.

关键词： α-Glucosidase Carbon dots Fluorescent sensor Inhibitor β-Cyclodextrin

Assembling Fe_(2)O_(3)/BiOCl Composite for Highly Effective Degradation of Water Pollutants under Visible-Light Irradiation

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2022年第1期24卷 59-67页

作者： liu xiaoqing Wang Zisha Hu Yuxing Wang Haifang School of Environment and Safety Engineering North University of ChinaTaiyuan 030051 Beijing Aerospace Institute for Metrology and Measurement Technology Beijing 100076

Fe_(2)O_(3)was synthesized by the solvothermal method,and the synthesized Fe_(2)O_(3)was added in the process of preparing BiOCl by hydrolysis,and then Fe_(2)O_(3)/BiOCl photocatalytic materials with different composite ratios were prepared.The optimal Fe_(2)O_(3)/BiOCl(1Fe/50Bi)sample showed a highest photocatalytic efficiency for cationic dyes(Rhodamine B)and anionic dye(methyl orange)degradation irradiated with visible light,as compared with that of a bare BiOCl catalyst.Meanwhile,radical capturing experiments indicated that the photo-induced holes(h^(+)) is the main active species.X-ray powder diffraction and ultraviolet-visible diffuse reflectance spectroscopy were used to characterize the structural and optical properties,which proved that Fe_(2)O_(3)was successfully composited to the BiOCl surface and effectively reduced the bandgap of BiOCl.More importantly,the optimal 1Fe/50Bi sample shows the highest photocatalytic efficiency for tetracycline(TC)degradation(98%)irradiated with visible light,as compared with that of a bare BiOCl catalyst.Consequently,the Fe_(2)O_(3)/BiOCl photocatalyst have potential applications in environmental purification.

关键词： Fe_(2)O_(3) BiOCl composite photocatalytic

Pyrolysis Mechanism of a Cyclotriphosphazene-Based Flame-Retardant Epoxy Resin by ReaxFF Molecular Dynamics

在线全文

学校读者我要写书评

暂无评论

中国炼油与石油化工:英文版 2023年第3期25卷 136-152页

作者： Jiang Shuaijun Meng Weifeng Wan Yongqing Qin Weihua liu xiaoqing Lan Yanhua School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China

Cyclotriphosphazene derivatives can effectively improve the flame retardancy and fire safety of epoxy resins(EPs)via their influence on the pyrolysis process.In this work,the effects of hexa(5-methyl-2-pyridinoxyl)cyclotriphosphazene(HMPOP)incorporation on the initial pyrolysis of an EP at 500–3500 K were studied using the ReaxFF method.The pyrolysis fragments,initial reaction pathways,and main products were identified for the EP and EP/HMPOP composites.The activation energies were derived by fitting the weight percentage curves for solid species during the pyrolysis reactions and the obtained values were in good agreement with experimental data.The initial EP pyrolysis reactions included four major decomposition modes,which primarily involved the cleavage of C–O and C–N bonds.The main pyrolysis products were H_(2)O,CO,C_(2)H_(4),and CH_(2)O.HMPOP bonded with the oxygen-containing fragments to form larger molecular fragments and reduced the amounts of C_(0)–C_(4) products,especially that of the harmful gas CH_(2)O.Thus,HMPOP promoted the formation of carbon clusters and reduced the generation of combustible gases,ultimately decreasing the capacity for fire propagation.

关键词： epoxy cyclotriphosphazene ReaxFF pyrolysis flame retardancy

Energy-dispersive X-ray Spectroscopy for the Quantitative Analysis of Pyrite Thin Specimens

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1304-1310页

作者： LUO Tingting GUO Yi DENG Zhao liu xiaoqing SUN Zhenya QI Yanyuan YANG Meijun Center for Materials Research and Analysis Testing Wuhan University of Technology Wuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070Wuhan

To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantitative analysis of pyrite materials.Additionally,the k factor of pyrite is calculated experimentally.To develop an appropriate non-standard quantitative analysis model for pyrite materials,the experimentally calculated k factor is compared with that estimated from the non-standard quantitative analytical model of the instrument software.The experimental findings demonstrate that the EDS attached to a TEM can be employed for precise quantitative analysis of micro-and nanoscale regions of pyrite materials.Furthermore,it serves as a reference for improving the results of the EDS quantitative analysis of other sulfides.

关键词： analytical transmission electron microscopy(AEM) energy dispersive X-ray spectroscopy(EDS) pyrite thin specimen quantitative analysis

Epidemiological Characteristics of Human Parainfluenza Viruses Infections-China,2019-2023

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2024年第12期6卷 235-241,I0003,I0004页

作者： Yixuan Gao Yingwei Ma Daxing Feng Feng Zhang Biao Wang xiaoqing liu Bing Zhu Hui Xie Linqing Zhao Xiaoru Long Ying Chen Bing Wang Jie Jiang Zhen Zhu Yan Zhang Aili Cui Baicheng Xia Naiying Mao National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Precision Medicine Research Center Children’s Hospital of ChangchunChangchun CityJilin ProvinceChina Henan Provincial Center for Disease Control and Prevention Zhengzhou CityHenan ProvinceChina Laboratory of Viral Diseases Qingdao Municipal Centre for Disease Control and PreventionQingdao CityShandong ProvinceChina Virus Laboratory Gansu Provincial Center for Disease Control and PreventionLanzhou CityGansu ProvinceChina Jiangxi Provincial Center for Disease Control and Prevention Nanchang CityGansu ProvinceChina Virus Laboratory Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhou CityGuangdong ProvinceChina Institute for Immunization and Prevention Beijing Center for Disease Prevention and ControlAcademy for Preventive MedicineInstitute of Tuberculosis Control Research and PreventionBeijingChina Laboratory of Virology Beijing Key Laboratory of Etiology of Viral Diseases in ChildrenCapital Institute of PediatricsBeijingChina Department of Infection Children’s Hospital of Chongqing Medical UniversityChongqingChina Inner Mongolia Autonomous Region Comprehensive Center for Disease Control and Prevention Hohhot CityInner Mongolia Autonomous RegionChina Shenyang Prefecture Center for Disease Control and Prevention Shenyang CityLiaoning ProvinceChina

Introduction:A retrospective study based on sentinel surveillance was conducted in 10 provinciallevel administrative divisions(PLADs)in China to enhance the understanding of the epidemiological characteristics of human parainfluenza viruses(HPIVs).Methods:From January 2019 to June 2023,respiratory specimens were collected from individuals with acute respiratory infections(ARIs)and screened for four HPIVs serotypes and other common respiratory viruses using multiplex real-time polymerase chain reaction(PCR).This study analyzed the association of HPIVs infections with seasonal patterns,geographical distribution,demographic profiles,clinical features,and co-infection status.Results:During the study period,a total of 12,866 ARIs were included.The overall detection rate of HPIVs was 6.15%,varying from 5.04%in 2022 to 9.70%in 2020.The median age of HPIVs-infected patients was 3 years.HPIV2 was more prevalent among individuals aged 5–17 years(42.57%),while HPIV4 was more common in those over 65 years(12.24%).HPIV3(54.16%)and HPIV1(27.18%)were the predominant serotypes,and their prevalence exhibited significant seasonal fluctuations postcoronavirus disease 2019(COVID-19)pandemic.The peak of HPIV3 shifted three months later in 2020 compared to 2019 and returned to a summer peak thereafter.Two peaks of HPIV1 were observed in 2021 following the peak of HPIV3.Additionally,coinfections were frequent in HPIVs cases(overall rate:22.12%),with human rhinovirus being the most common co-infecting virus.Conclusions:The prevalence of HPIVs in China was predominantly due to HPIV3 and HPIV1,and their seasonal patterns were altered by pandemic restrictions.Hence,continuous surveillance of HPIVs is essential.

关键词： prevalence seasonal Human

疏水二氧化硅粒子的制备及超疏水改性聚氨酯树脂

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

高分子材料科学与工程 2024年第1期40卷 8-16页

作者：刘晓庆杨进华南理工大学轻工科学与工程学院造纸与污染控制国家工程研究中心制浆造纸国家重点实验室广东广州510640

为了制备具有稳定超疏水性能的改性水性聚氨酯树脂,受“荷叶效应”的启迪,以十二烷基三乙氧基硅烷(DTES)的碱性水解反应为基础,通过SiO_(2)粒子表面硅羟基的接枝反应,在其表面引入低表面能的长链烷烃结构,制备了微胶囊包覆型的具有疏水... 详细信息

为了制备具有稳定超疏水性能的改性水性聚氨酯树脂,受“荷叶效应”的启迪,以十二烷基三乙氧基硅烷(DTES)的碱性水解反应为基础,通过SiO_(2)粒子表面硅羟基的接枝反应,在其表面引入低表面能的长链烷烃结构,制备了微胶囊包覆型的具有疏水效应的二氧化硅粒子。通过红外光谱、X射线衍射、扫描电镜等手段表征其结构,确定了疏水改性粒子的制备方法和规律。将自制改性SiO_(2)粒子与水性聚氨酯树脂(WPU)进行物理共混,制备出具有超疏水性能的水性聚氨酯涂料。采用差示扫描量热分析和热重分析表征涂料的共混性能及耐热性能,采用扫描电镜和原子力显微镜量化分析涂层特征及表面形貌,采用接触角测试表征水性涂层的超疏水性能及表面能的变化。结果显示,自制疏水粒子迁移到环氧树脂表面,通过化学作用和物理缠结形成强烈的界面结合,使其表面微纳结构稳定且持久,结合长链烷烃的低表面能修饰,赋予共混树脂超疏水性能,接触角达到158°,而涂层的均方根粗糙度(Rq)由纯WPU的7.82 nm增大至101 nm,平均粗糙度(Ra)由6.24 nm增大至77.9 nm,表面粗糙度大大提升。将水性树脂的水性化制备与超疏水性能相结合,制备了绿色环保具有自清洁效应的水性聚氨酯,而形成的特殊的树脂涂层表面在苛刻环境中保持了结构的稳定性和持久性,表现出优异的耐磨和耐化学腐蚀性能。

关键词：粒子设计水性聚氨酯超疏水表面能微胶囊包覆

Assembling Superfine Bi_(3)TaO_(7) Particles into 2D Fe_(2)O_(3) Nanosheets for Enhanced Usability to Aqueous Tetracycline Residues

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2022年第2期24卷 147-158页

作者： liu xiaoqing Cheng Hongjun Wang Zisha Zhang Jian Lan Yanhua Wang Xiaojing School of Environment and Safety Engineering North University of ChinaTaiyuan030051 Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical EngineeringInner Mongolia UniversityHuhhotInner Mongolia010021

Composites of 2D/0D Fe_(2)O_(3)-Bi_(3)TaO_(7)(FO-BTO)prepared by a hydrothermal method in which superfine Bi_(3)TaO_(7) particles were mounted onto lamellae of Fe_(2)O_(3) sheets could efficiently remove aqueous tetracycline(TC)residues.The optimal composite FO-3BTO had a TC removal rate of 95%in 120 min under solar light,and its overall properties were better than those of reported photocatalysts.According to XRD,HRTEM,XPS,SEM,PL,EIS,and photocurrent tests,Fe_(2)O_(3) and Bi_(3)TaO_(7) composites formed on effective S-scheme heterojunctions,and the tight contact structure contributed to the increase in efficiency of aqueous TC residue removal.

关键词： Bi_(3)TaO_(7) Fe_(2)O_(3) S-scheme heterojunction Tetracycline degradation Photocatalytic efficiency

基于VMD-XGBoost-GRU模型的危岩体变形预测

在线全文

学校读者我要写书评

暂无评论

水利水电科技进展 2024年第2期44卷 92-98页

作者：许秋鸿刘晓青河海大学水利水电学院江苏南京210098

针对以往对危岩体监测数据前处理效果不佳的问题,提出了一种用于危岩体变形预测的VMD-XGBoost-GRU组合模型。该模型采用变分模态分解(VMD)和样本熵理论将危岩体变形数据分解成多个子序列,利用XGBoost算法提取重要的模型因子实现特征降维... 详细信息

针对以往对危岩体监测数据前处理效果不佳的问题,提出了一种用于危岩体变形预测的VMD-XGBoost-GRU组合模型。该模型采用变分模态分解(VMD)和样本熵理论将危岩体变形数据分解成多个子序列,利用XGBoost算法提取重要的模型因子实现特征降维,通过门控循环单元(GRU)神经网络对危岩体变形进行预测。以某水电站右坝肩陡壁上的危岩体变形预测为例,将VMD-XGBoost-GRU组合模型与BP、GRU和VMD-XGBoost-BP 3种模型进行对比与分析,结果表明,VMD-XGBoost-GRU组合模型在危岩体变形预测方面具有较高精度,可为危岩体安全稳定状态评价提供技术依据。

关键词：危岩体 VMD 样本熵 XGBoost GRU 变形预测模型