检索结果-南通市图书馆

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang xu Ying-Nan Zhao Yao Yu qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in hexane.This catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of 20000.Furthermore,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene polymerization.These characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer yield.The resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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

Improved photocatalytic performance of acetaldehyde degradation via crystal plane regulation on truncated octahedral CeO2

引用

Rare Metals 2024年第5期43卷 2026-2038页

作者： Bin xu Lu Jia Hui Yang Yue Wang Si-Yu Fan Sai-Sai Yuan qi-Tao Zhang Ming Zhang Teruhisa Ohno School of Chemistry and Chemical Engineering Yangzhou University College of Environmental Science and Engineering Yangzhou University Department of Applied Chemistry Faculty of EngineeringKyushu Institute of Technology School of Environmental and Chemical Engineering Jiangsu University of Science and Technology National & Local Joint Engineering Research Center for Mineral Salt Deep Utilization Huaiyin Institute of Technology School of Materials Science and Engineering Henan University of Science and Technology International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale Optoelectronics Shenzhen University

In this study,the truncated octahedral Ce O2（Ce O2-to） with special morphology was prepared by the solvothermal method with oleic acid （OA） and oleamine（OM） as the morphology-directing agents.High-resolution transmission electron microscopy （HRTEM） results show that Ce O2-to exposes composite{100}and{111}facets,while Ce O2cubic （Ce O2-c） and Ce O2octahedral （Ce O2-o）only expose single crystal facets of{100}plane and{111}plane,respectively.Interestingly,this Ce O2-to photocatalyst exhibits remarkable photooxidation performance of gaseous acetaldehyde （CH3CHO） degradation,in which CO2generation value reaches 1.78 and 7.97-times greater than that of Ce O2-c and Ce O2-o,respectively.In addition,the active species trapping experiment signifies that superoxide （·O2-） and holes （h+） are the main reactive substances during the CH3CHO degradation process,and the electron paramagnetic resonance （EPR） spectra indicates that the former is the major contributor.Notably,the electron transfer mechanism between Ce O2-to{100}and{111}facets and the surface oxygen adsorption ability are revealed via density functional theory （DFT） calculations.It is also confirmed that{100}facets are more conducive to the absorption of acetaldehyde than{111}facets.Finally,a reasonable mechanism for improved photocatalytic CH3CHO degradation on Ce O2-to is proposed based on relevant experiments and DFT calculations.This study demonstrates that the systematic development of surface homojunction structured photocatalysts can efficiently increase the degradation activity for volatile organic compounds （VOCs）.It also offers additional direction for optimizing the photocatalytic activity of other ceriumbased photocatalysts.

关键词： Truncated octahedral CeO 2 (CeO 2 -to) Composite crystal faces Surface energy level Efficient electron transfer

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Stark splitting of intense red emission for Er^(3+)in O_(h) symmetry sites realizing optical temperature sensing in biological applications

引用

Rare Metals 2024年第3期43卷 1263-1274页

作者： Yue Guo Lin-Jun qin Jing xu Xiao-Ping Jiang Xiao-Yu Yue Yi Hou Hao Shi Li-Xi Wang qi-Tu Zhang Collage of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing211816China

Optical temperature sensing based on the fluorescence intensity ratio(FIR)of red emission for lanthanide ions holds significant relevance in non-contact temperature measurement for biological application.In this study,the perovskite-structured KZnF_(3)is utilized as a host material for Er^(3+)to achieve a high-purity upconversion(UC)red emission.The observed Stark splitting of the red emission peak provides evidence of the energy level splitting of Er^(3+).Group theory is employed to decompose the spectral branching of Er^(3+)under the point group symmetry of KZnF_(3),allowing for the derivation of Stark splitting energy levels induced by the crystal field effect.The optical temperature-sensing behavior of the red UC luminescence was investigated,specifically examining the FIR of the splitting sub-peaks,which exhibited an exponential relationship with temperature.The KZnF_(3):Yb^(3+),Er^(3+)demonstrated a relative sensitivity(S_(r))of 0.00182%·K^(-1)at 298 K,highlighting its excellent response to temperature.Ex vivo bio-thermometry experiments conducted on chicken breast validated the material's ability to penetrate biological tissues and showed its significant sensitivity of the FIR to temperature.These results establish KZnF_(3):Yb^(3+),Er^(3+)as a promising material for optical thermometry in various biological applications.

关键词： KZnF_(3) Er^(3+) Upconversion luminescence Stark splitting Temperature sensing

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 expression mechanism of programmed cell death 1 ligand 1 and its role in immunomodulatory ability of mesenchymal stem cells

引用

Chinese Journal of Traumatology 2024年第1期27卷 1-10页

作者： Zhuo Chen Meng-Wei Yao Xiang Ao qing-Jia Gong Yi Yang Jin-Xia Liu qi-Zhou Lian Xiang xu Ling-Jing Zuo Department of Stem Cell&Regenerative Medicine State Key Laboratory of TraumaBurn and Combined InjuryDaping HospitalArmy Medical UniversityChongqing400042China College of Basic Medical Sciences Army Medical UniversityChongqing400038China Department of Orthopedics 953 Hospital of PLAShigatse Branch of Xinqiao HospitalArmy Medical UniversityShigatse857000Tibet Autonomous RegionChina Department of Rheumatology and Immunology Daping HospitalArmy Medical UniversityChongqing400042China Department of Obstetrics and Gynecology Chongqing People's HospitalChongqing401121China Department of Medicine Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Department of Nuclear Medicine The First People's Hospital of Yunnan provinceAffiliated Hospital of Kunming University of Science and TechnologyKunming650034China

Programmed cell death 1 ligand 1(PD-L1)is an important immunosuppressive molecule,which inhibits the function of T cells and other immune cells by binding to the receptor programmed cell death-1.The PD-L1 expression disorder plays an important role in the occurrence,development,and treatment of sepsis or other inflammatory diseases,and has become an important target for the treatment of these diseases.Mesenchymal stem cells(MSCs)are a kind of pluripotent stem cells with multiple differentiation potential.In recent years,MSCs have been found to have a strong immunosuppressive ability and are used to treat various inflammatory insults caused by hyperimmune diseases.Moreover,PD-L1 is deeply involved in the immunosuppressive events of MSCs and plays an important role in the treatment of various diseases.In this review,we will summarize the main regulatory mechanism of PD-L1 expression,and discuss various biological functions of PD-L1 in the immune regulation of MSCs.

关键词： PD-L1 MSCs Immunomodulation

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

Enabling an Inorganic-Rich Interface via Cationic Surfactant for High-Performance Lithium Metal Batteries

引用

Nano-Micro Letters 2024年第8期16卷 1-17页

作者： Zejun Sun Jinlin Yang Hongfei xu Chonglai Jiang Yuxiang Niu xu Lian Yuan Liu Ruiqi Su Dayu Liu Yu Long Meng Wang Jingyu Mao Haotian Yang Baihua Cui Yukun Xiao Ganwen Chen qi Zhang Zhenxiang Xing Jisheng Pan Gang Wu Wei Chen Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore Agency for Science Technology and Research(A*STAR)Institute of High-Performance Computing1 Fusionopolis Way#16‑16 ConnexisSingapore 138632Singapore Department of Physics National University of Singapore2 Science Drive 3Singapore 117542Singapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207People’s Republic of China Agency for Science Technologyand Research(A*STAR)Institute of Materials Research and EngineeringInnovis2 Fusionopolis Way#08‑03Singapore 138634Singapore

An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium bromide(CTAB),a cationic surfactant,is adopted to draw more anions into EDL by ionic interactions that shield the repelling force on anions during lithium plating.In situ electrochemical surface-enhanced Raman spectroscopy results combined with molecular dynamics simulations validate the enrichment of NO_(3)^(−)/FSI−anions in the EDL region due to the positively charged CTA^(+).In-depth analysis of SEI structure by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry results confirmed the formation of the inorganic-rich SEI,which helps improve the kinetics of Li^(+)transfer,lower the charge transfer activation energy,and homogenize Li deposition.As a result,the Li||Li symmetric cell in the designed electrolyte displays a prolongated cycling time from 500 to 1300 h compared to that in the blank electrolyte at 0.5 mA cm^(-2) with a capacity of 1 mAh cm^(-2).Moreover,Li||LiFePO_(4) and Li||LiCoO_(2) with a high cathode mass loading of>10 mg cm^(-2) can be stably cycled over 180 cycles.

关键词： Cationic surfactant Lithium nitrate additive Solid-electrolyte interphase Electric double layer Lithium metal batteries

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

Predicting short-term major postoperative complications in intestinal resection for Crohn’s disease:A machine learning-based study

引用

World Journal of Gastrointestinal Surgery 2024年第3期16卷 717-730页

作者： Fang-Tao Wang Yin Lin Xiao-qi Yuan Ren-Yuan Gao Xiao-Cai Wu Wei-Wei xu Tian-qi Wu Kai Xia Yi-Ran Jiao Lu Yin Chun-qiu Chen Diagnostic and Treatment Center for Refractory Diseases of Abdomen Surgery Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200072China

BACKGROUND Due to the complexity and numerous comorbidities associated with Crohn’s disease(CD),the incidence of postoperative complications is high,significantly impacting the recovery and prognosis of patients.Consequently,additional stu-dies are required to precisely predict short-term major complications following intestinal resection(IR),aiding surgical decision-making and optimizing patient care.AIM To construct novel models based on machine learning(ML)to predict short-term major postoperative complications in patients with CD following IR.METHODS A retrospective analysis was performed on clinical data derived from a patient cohort that underwent IR for CD from January 2017 to December 2022.The study participants were randomly allocated to either a training cohort or a validation cohort.The logistic regression and random forest(RF)were applied to construct models in the training cohort,with model discrimination evaluated using the area under the curves(AUC).The validation cohort assessed the performance of the constructed models.RESULTS Out of the 259 patients encompassed in the study,5.0%encountered major postoperative complications(Clavien-Dindo≥III)within 30 d following IR for CD.The AUC for the logistic model was 0.916,significantly lower than the AUC of 0.965 for the RF model.The logistic model incorporated a preoperative CD activity index(CDAI)of≥220,a diminished preoperative serum albumin level,conversion to laparotomy surgery,and an extended operation time.A nomogram for the logistic model was plotted.Except for the surgical approach,the other three variables ranked among the top four important variables in the novel ML model.CONCLUSION Both the nomogram and RF exhibited good performance in predicting short-term major postoperative complic-ations in patients with CD,with the RF model showing more superiority.A preoperative CDAI of≥220,a di-minished preoperative serum albumin level,and an extended operation time might be the most crucial variables.The findings of this study can assist clinicians in

关键词： Crohn’s disease Postoperative complications Nomogram Random forest Intestinal resection

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

Analysis of blocking slurry diffusion parameters for a new self-starting drainage anchor cable

引用

Journal of Earth Science 2024年

作者： WANG xu GE qi Lü Chengcheng SHU Junwei SUN Hongyue Sino-Italy Ningbo Ecological Park Holding Group Co. Ltd Ocean College Zhejiang University College of Civil Engineering and Architecture Zhejiang University School of Civil Engineering Nanjing Forestry University

A new self-starting drainage anchor that combines prestressed anchor cables with self-starting drainage is proposed. The novelty of the self-starting drainage method is the realization of the drainage and anchoring in the one inclined borehole. Reduction in the number of boreholes can greatly decrease the construction cost and duration of the project. The adverse effect of drilling construction disturbance on the slope is reduced. To tackle the possible blockage of the drainage cavity due to slurry leakage during the solidification process after finishing grouting in the blocking section. To this end， a theoretical equation for the slurry diffusion radius under slurry self-weight pressure boundary conditions is deduced. The result is verified for precision through comparison with numerical simulation. The findings reveal that the permeability coefficient of rock and soil mass makes the most significant impact on the slurry diffusion radius， succeeded by the length of the grouting blocking section， slurry initial setting time， and drilling inclination in descending order of influence. With the 5% mass ratio of a "711" type slurry quick-setting agent， the maximum slurry diffusion radius can be reduced from 0.925m to 0.449m， a reduction of 0.476m， which is comparatively more recommended.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Roles of combined femoral and acetabular anteversion in pathological changes of hip dysplasia and hip reconstructive surgery

引用

World Journal of Orthopedics 2024年第5期15卷 390-399页

作者： Can Liu Zheng xu Jian-Fa Zeng Zhen-qi Song Yu-Yin Xie Zhong-Wen Tang Jie Wen Sheng Xiao Department of Anatomy Hunan Normal University School of MedicineChangsha 410003Hunan ProvinceChina Department of Pediatric Orthopedics Hunan Provincial People's HospitalThe First Affiliated Hospital of Hunan Normal UniversityChangsha 410013Hunan ProvinceChina

Combined femoral and acetabular anteversion is the sum of femoral and acetabular anteversion,representing their morphological relationship in the axial plane.Along with the increasing understanding of hip dysplasia in recent years,numerous scholars have confirmed the role of combined femoral and acetabular anteversion in the pathological changes of hip dysplasia.At present,the reconstructive surgery for hip dysplasia includes total hip replacement and redirectional hip preservation surgery.As an important surgery index,combined femoral and acetabular anteversion have a crucial role in these surgeries.Herein,we discuss the role of combined femoral and acetabular anteversion in pathological changes of hip dysplasia,total hip replacement,and redirectional hip preservation surgery.

关键词： Combined anteversion Femoral anteversion Acetabular anteversion Hip dysplasia Hip preservation surgery Total hip replacement

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

Effective time, correction speed and termination time of hemiepiphysiodesis in children

引用

World Journal of Orthopedics 2024年第1期15卷 1-10页

作者： Jian-Fa Zeng Yu-Yin Xie Can Liu Zhen-qi Song Zheng xu Zhong-Wen Tang Jie Wen Sheng Xiao Department of Pediatric Orthopedics Hunan Provincial People's HospitalThe First Affiliated Hospital of Hunan Normal UniversityChangsha 410013Hunan ProvinceChina Department of Anatomy Hunan Normal University school of MedicineChangsha 410003Hunan ProvinceChina

In children with asymmetric growth on the medial and lateral side of limbs,if there still remains growth potential,the guided growth technique of hemiepiphysiodesis on one side of the epiphysis is recognized as a safe and effective method.However,when the hemi-epiphysiodesis start to correct the deformities,how many degrees could hemi-epiphysiodesis bring every month and when to remove the hemi-epiphysiodesis implant without rebound phenomenon are still on debate.This article reviews the current studies focus on the effective time,correction speed and termination time of hemi-epiphysiodesis.

关键词： Hemi-epiphysiodesis Percutaneous epiphysiodesis Transphyseal screws Eight plate

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

Postoperative encapsulated hemoperitoneum in a patient with gastric stromal tumor treated by exposed endoscopic full-thickness resection: A case report

引用

World Journal of Gastrointestinal Surgery 2024年第2期16卷 601-608页

作者： Hui-Fei Lu Jing-Jing Li De-Bin Zhu Li-qi Mao Li-Fen xu Jing Yu Lin-Hua Yao Department of Gastroenterology the First People’s Hospital of HuzhouHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Gastric stromal tumors,originating from mesenchymal tissues,are one of the most common tumors of the digestive tract.For stromal tumors originating from the muscularis propria,compared with conventional endoscopic submucosal dissection(ESD),endoscopic full-thickness resection(EFTR)can remove deep lesions and digestive tract wall tumors completely.However,this technique has major limitations such as perforation,postoperative bleeding,and post-polypectomy syndrome.Herein,we report a case of postoperative serous surface bleeding which formed an encapsulated hemoperitoneum in a patient with gastric stromal tumor that was treated with exposed EFTR.Feasible treatment options to address this complication are described.CASE SUMMARY A 47-year-old male patient had a hemispherical protrusion found during gastric endoscopic ultrasonography,located at the upper gastric curvature adjacent to the stomach fundus,with a smooth surface mucosa and poor mobility.The lesion was 19.3 mm×16.1 mm in size and originated from the fourth ultrasound layer.Computed tomography(CT)revealed no significant evidence of lymph node enlargement or distant metastasis.Using conventional ESD technology for mucosal pre-resection,exposed EFTR was performed to resect the intact tumor in order to achieve a definitive histopathological diagnosis.Based on its morphology and immunohistochemical expression of CD117 and DOG-1,the lesion was proven to be consistent with a gastric stromal tumor.Six days after exposed EFTR,CT showed a large amount of encapsulated fluid and gas accumulation around the stomach.In addition,gastroscopy suggested intracavitary bleeding and abdominal puncture drainage indicated serosal bleeding.Based on these findings,the patient was diagnosed with serosal bleeding resulting in encapsulated abdominal hemorrhage after exposed EFTR for a gastric stromal tumor.The patient received combined treatments,such as hemostasis under gastroscopy,gastrointestinal decompression,and abdominal drainage.All examinations were normal within six

关键词： Exposed endoscopic full-thickness resection Gastric stromal tumors Hemoperitoneum Abdominal infection Complication Postoperative bleeding Case report

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：