检索结果-南通市图书馆

Impact of Polymer matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： yu Wu xin Cheng Huan Hu Shui Hu Zhimin ma Zhiyong ma Beijing Advanced Innovation Center for Soft matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic polymers based on non-covalent changes have attracted much attention recently.Herein,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) process.PhMz-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),respectively.In the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@Pma-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds matter.Furthermore,under stretching,external force can tune the emission of the PhMz=2A@Pma-2-EA sample from K* to E* state.Though external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating environment.DFT calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/off.Thus,PhMz-NH2-OH@PU and PhMz=2A@Pma-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to force.This study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

来源：

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

Floating plants reduced methane fluxes from wetlands by creating a habitat conducive to methane oxidation

引用

Journal of Environmental Sciences 2024年第1期135卷 149-160页

作者： Fuwei Wang Songhe Zhang Xiuren Hu xin Lv Min Liu yu ma Benjamin manirakiza Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China College of Environment Hohai UniversityNanjing 210098China China machinery International Engineering Desigh and Research Institute co. Ltd.East China Regional CenterNanjing 210008China

Wetlands are one of the important natural sources of atmospheric methane (CH_4),as an important part of wetlands,floating plants can be expected to affect methane release.However,the effects of floating plants on methane release are limited.In this study,methane fluxes,physiochemical properties of the overlying water,methane oxidation potential and rhizospheric bacterial community were investigated in simulated wetlands with floating plants Eichhornia crassipes,Hydrocharis dubia,and Trapa natans.We found that E.crassipes,H.dubia,and T.natans plants could inhibit 84.31%-97.31%,4.98%-88.91%and 43.62%-92.51%of methane fluxes at interface of water-atmosphere compared to Control,respectively.Methane fluxes were negatively related to nutrients concentration in water column but positively related to the aerenchyma proportions of roots,stems,and leaves.At the same biomass,root of E.crassipes (36.44%) had the highest methane oxidation potential,followed by H.dubia (12.99%) and T.natans (11.23%).Forty-five bacterial phyla in total were identified on roots of three plants and 7 bacterial genera (2.10%-3.33%) were known methanotrophs.Type I methanotrophs accounted for 95.07%of total methanotrophs.The pmoA gene abundances ranged from 1.90×10^(16)to 2.30×10^(18)copies/g fresh weight of root biofilms.Abundances of pmoA gene was significantly positively correlated with environmental parameters.Methylotrophy (5.40%) and methanotrophy (3.75%) function were closely related to methane oxidation.This study highlights that floating plant restoration can purify water and promote carbon neutrality partially by reducing methane fluxes through methane oxidation in wetlands.

关键词： Floating plants Methane fluxes Aerenchyma Methanotrophs

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

引用

Food Science and Human Wellness 2024年第3期13卷 1543-1555页

作者： xin Wang Weiye Xiu Ye Han Zhili Wang yu Luo Yongqiang ma Heilongjiang Provincial Key Laboratory of Cereals and Comprehensive Processing of Cereal Resources College of Food EngineeringHarbin University of CommerceHarbin 150028China

Type 2 diabetes mellitus(T2DM)is a metabolic disease caused by a glycolipid metabolism disorder and isletβ-cell dysfunction.SCP-80-I is a biologically active water-soluble polysaccharide isolated from sweet corncob,an agricultural byproduct.The hypoglycemic effects of SCP-80-I on T2DM mice and its mechanisms were investigated in this study.SCP-80-I was found to significantly reduce blood glucose and lipid deposition levels in T2DM mice,as well as decrease serum leptin and increase adiponectin secretion.Interestingly,real time-polymerase chain reaction(RT-PCR)and Western blotting results revealed that SCP-80-I could regulate the expression of several glycolipid metabolisms and insulin secretion genes and proteins,including 5'-AMP-activated protein kinase(AMPK),carnitine palmitoyltransferase I(CPTI),and acetyl coenzyme A carboxylase(ACC)in the liver and AMPK,sirtuin1(Sirtl),peroxisome proliferator-activated receptorycoactivator-1(PGC-1α),and uncoupling protein 2(UCP2)in the pancreas.To have a hypoglycemic effect,SCP-80-1 regulated glycolipid metabolism and islet cell function in the liver by regulating the AMPK/AC C/CPT1 signaling pathway and the AMPK/Sirt1/PGC-1αand AMPK/Sirtl/UCP2 signaling pathways.These findings improve our understanding of polysaccharides derived from sweet corncob and the use of SCP-80-I in the production of hypoglycemic foods.

关键词： Sweet corn cob polysaccharide Type 2 diabetes Signal pathway 5’-AMP-activated protein kinase(AMPK)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of Aromatherapy on Physical and Mental Health of Cancer Patients Undergoing Radiotherapy and/or Chemotherapy: A Meta-Analysis

引用

Chinese Journal of Integrative Medicine 2024年第5期30卷 449-457页

作者： XIE Shuang-ran ma Liang XU xin-yu ZHOU Shu XIE Hui-miao XIE Chang-sheng The First Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053China Department of Medical Oncology Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical UniversityHangzhou 310007China Department of Dermatology the Third Xiangya HospitalCentral South UniversityChangsha 410013China Department of Famous Chinese Medicine Clinic the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310005China Department of Medical Oncology the First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310006China

Backgroup:Currently,aromatherapy is being increasingly utilized in clinical practice,particularly in managing the side effects associated with radiotherapy and chemoradiotherapy.However,it remains to be established whether aromatherapy can effectively alleviate these symptoms.Objective:To investigate the effects of aromatherapy on the physical and mental health of patients with cancer undergoing radiotherapy and chemotherapy.Methods:Seven databases were researched from inception until September 29,2023,including PubMed,Scopus,and Web of Science,Chinese National Knowledge Infrastructure,Wanfang database,China Biology Medicine disc and VIP Chinese Medical Journal Database.Review manager version 5.3 was utilized for data analysis.The Cochrane Risk of Bias tool RoB2 was employed to evaluate the quality of the literature included in the study.Evidence quality rating was assessed using the Grading of Recommendations Assessment,Development,and Evaluation(GRADE) approach through the GRADEpro GDT online tool.Results:Nineteen studies involving 1,541 patients were included.Aromatherapy can alleviate nausea [relative risk(RR)=0.64,95% confidence interval(CI):0.53 to 0.78,Pmay not have a significant effect on anxiety.The risk of bias was high in the included studies using the Cochrane Risk of Bias tool RoB2,and no studies were considered to be of high grade according to the GRADE system.Conclusions:Aromatherapy is an efficacious,safe and economic adjunctive therapy for cancer patien

关键词： aromatherapy cancer chemoradiotherapy physical psychological

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Calcium-chelating peptides from rabbit bone collagen:characterization,identification and mechanism elucidation

引用

Food Science and Human Wellness 2024年第3期13卷 1485-1493页

作者： Fuhuan yuan yu Fu Liang ma Hankun Zhu Yong yu xin Feng Yi Sun Hongjie Dai xin Liu Zhengfang Liu yuhao Zhang College of Food Science Southwest UniversityChongqing 400715China Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing Chongqing 400715China Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University) Ministry of EducationChongqing 400715China Angel Yeast Co. Ltd.Yichang 443003China

This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides.

关键词： Rabbit bone Collagen peptide Peptide-calcium chelate Chelation mechanism Liquid chromatography-tandem mass(LC-MS/MS)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Efficacy and safety of perioperative therapy for locally resectable gastric cancer:A network meta-analysis of randomized clinical trials

引用

World Journal of Gastrointestinal Oncology 2024年第3期16卷 1046-1058页

作者： Zi-yu Kuang Qian-Hui Sun Lu-Chang Cao xin-Yi ma Jia-Xi Wang Ke-xin Liu Jie Li Graduate College Beijing University of Traditional Chinese MedicineBeijing 100029China Oncology Department Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing 100053China

BACKGROUND Gastric cancer(GC)is the fifth most commonly diagnosed malignancy worldwide,with over 1 million new cases per year,and the third leading cause of cancer-related death.AIM To determine the optimal perioperative treatment regimen for patients with locally resectable GC.METHODS A comprehensive literature search was conducted,focusing on phase II/III randomized controlled trials(RCTs)assessing perioperative chemotherapy and chemoradiotherapy in treating locally resectable GC.The R0 resection rate,overall survival(OS),disease-free survival(DFS),and incidence of grade 3 or higher nonsurgical severe adverse events(SAEs)associated with various perioperative regimens were analyzed.A Bayesian network meta-analysis was performed to compare treatment regimens and rank their efficacy.RESULTS Thirty RCTs involving 8346 patients were included in this study.Neoadjuvant XELOX plus neoadjuvant radiotherapy and neoadjuvant CF were found to significantly improve the R0 resection rate compared with surgery alone,and the former had the highest probability of being the most effective option in this context.Neoadjuvant plus adjuvant FLOT was associated with the highest probability of being the best regimen for improving OS.Owing to limited data,no definitive ranking could be determined for DFS.Considering nonsurgical SAEs,FLO has emerged as the safest treatment regimen.CONCLUSION This study provides valuable insights for clinicians when selecting perioperative treatment regimens for patients with locally resectable GC.Further studies are required to validate these findings.

关键词： Gastric cancer Perioperative treatment Network meta-analysis Efficacy and safety

来源：

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

mapping soil organic matter in cultivated land based on multi-year composite images on monthly time scales

引用

Journal of Integrative Agriculture 2024年第4期23卷 1393-1408页

作者： Jie Song Dongsheng yu Siwei Wang Yanhe Zhao xin Wang Lixia ma Jiangang Li State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Agricultural and Rural Bureau of Luanping County Luanping 068250China Chinese Academy of Sciences University Beijing 100049China

Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance management.This study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly scale.We obtained 12 monthly synthetic Sentinel-2 images covering the study area from 2016 to 2021 through the Google Earth Engine(GEE)platform,and reflectance bands and vegetation indices were extracted from these composite images.Then the random forest(RF),support vector machine(SVM)and gradient boosting regression tree(GBRT)models were tested to investigate the difference in SOM prediction accuracy under different combinations of monthly synthetic variables.Results showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(Pmarch,April,October,and November.Secondly,in terms of single-monthly composite variables,the prediction accuracy was relatively poor,with the highest R^(2)value of 0.36 being observed in January.When monthly synthetic environmental variables were grouped in accordance with the four quarters of the year,the first quarter and the fourth quarter showed good performance,and any combination of three quarters was similar in estimation accuracy.The overall best performance was observed when all monthly synthetic variables were incorporated into the models.Thirdly,among the three models compared,the RF model was consistently more accurate than the SVM and GBRT models,achieving an R^(2)value of 0.56.Except for band 12 in December,the importance of the remaining bands did not exhibit significant differences.This research offers a new attempt to map SOM with high accuracy and fine spatial resolution based on monthly synthetic Sentinel-2 images.

关键词： soil organic matter Sentinel-2 monthly synthetic images machine learning model spatial prediction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Incorporation of source contributions to improve the accuracy of soil heavy metal mapping using small sample sizes at a county scale

引用

Pedosphere 2024年第1期34卷 170-180页

作者： Jie SONG xin WANG Dongsheng yu Jiangang LI Yanhe ZHAO Siwei WANG Lixia ma State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Chinese Academy of Sciences University Beijing 100049China Agricultural and Rural Bureau of Luanping County Luanping 068250China

Estimating heavy metal(HM) distribution with high precision is the key to effectively preventing Chinese medicinal plants from being polluted by the native soil. A total of 44 surface soil samples were gathered to detect the concentrations of eight HMs(As, Hg, Cu, Cr, Ni, Zn, Pb, and Cd) in the herb growing area of Luanping County, northeastern Hebei Province, China. An absolute principal component score-multiple linear regression(APCS-MLR) model was used to quantify pollution source contributions to soil HMs. Furthermore, the source contribution rates and environmental data of each sampling point were simultaneously incorporated into a stepwise linear regression model to identify the crucial indicators for predicting soil HM spatial distributions. Results showed that 88% of Cu, 72% of Cr, and 72% of Ni came from natural sources;50% of Zn, 49% of Pb, and 59% of Cd were mainly caused by agricultural activities;and 44% of As and 56% of Hg originated from industrial activities. When three-type(natural, agricultural, and industrial) source contribution rates and environmental data were simultaneously incorporated into the stepwise linear regression model, the fitting accuracy was significantly improved and the model could explain 31%–86% of the total variance in soil HM concentrations. This study introduced three-type source contributions of each sampling point based on APCS-MLR analysis as new covariates to improve soil HM estimation precision, thus providing a new approach for predicting the spatial distribution of HMs using small sample sizes at the county scale.

关键词： absolute principal component score-multiple linear regression Chinese herbal medicine influencing factors spatial distribution stepwise multiple regression

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The size effect and analogous boundary states in a circular non-Hermitian chain

引用

Communications in Theoretical Physics 2024年第2期76卷 157-165页

作者： xin-yu ma Yi-Han Guan Qiao-Nan Li Ai-Lei He Lu Qi School of Physical Science and Technology Yangzhou UniversityYangzhou 225002China

We investigate the size effect and boundary states based on a circular non-Hermitian chain under the nonreciprocal intra-cell coupling and inter-cell coupling regimes.We find that the circular non-Hermitian chain exhibits an even–odd effect on the unit cell corresponding to a large chain,which is different from the open non-Hermitian chain only exhibiting the same effect for a small chain.Moreover,we find that the originally localized bulk states become totally extended via designing the boundary coupling strength appropriately.The extended bulk states reveal the fact of the disappearance of the non-Hermitian skin effect.In particular,we show that the circular non-Hermitian chain also possesses the analogous edge states under some parameter regimes,which is pretty counterintuitive since the circular chain usually cannot define a boundary.Our investigations supply the different non-Hermitian phenomena in a circular non-Hermitian chain.

关键词： boundary states non-Hermitian chain topological state

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

引用

Research 2024年第1期2023卷 651-662页

作者： Jian yu Zhong-Lin Wang Tianwei ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life cycle.However,because of limited performance,existing systems do not lend themselves to practical implementation.Although it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive mixing.Here,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the electrodes.Our findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：