检索结果-南通市图书馆

MISCIBILITY,CRYSTALLIZATION AND MECHANICAL PROPERTIES OF PPC/PBS BLENDS

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 Journal of Polymer Science 2007年第6期25卷 589-597页

作者： Hui-liang zhang Xiao-hong Sun Qing-yong Chen Min-qiao ren zhi-hao zhang Hong-fang zhang zhi-shen Mo State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Graduate School of Chinese Academy of Science Changchun 130022 China

In this paper, melt blends of poly（propylene carbonate）（PPC） with poly（butylene succinate）（PBS） were characterized by dynamic mechanical analysis （DMA）, differential scanning calorimetry （DSC）, tensile testing, wide-angle X-ray diffraction （WAXD）, polarized optical microscopy and thermogravimetric analysis （TGA）. The results indicated that the glass transition temperature of PPC in the 90/10 PPC/PBS blend was decreased by about 11 K comparing with that of pure PPC. The presence of 10% PBS was partially miscible with PPC. The 90/10 PPC/PBS blend had better impact and tensile strength than those of the other PPC/PBS blends. The glass transition temperature of PPC in the 80/20, 70/30, and 60/40 PPC/PBS blends was improved by about 4.9 K, 4.2 K, and 13 K comparing with that of pure PPC, respectively; which indicated the immiscibility between PPC and PBS. The DSC results indicated that the crystallization of PBS became more difficult when the PPC content increased. The matrix of PPC hindered the crystallization process of PBS. While the content of PBS was above 20%, significant crystallization-induced phase separation was observed by polarized optical microscopy. It was found from the WAXD analysis that the crystal structure of PBS did not change, and the degree of crystallinity increased with increasing PBS content in the PPC/PBS blends.

关键词： Poly(propylene carbonate) Poly(butylene succinate) Miscibility Crystallization Mechanical properties.

Risk stratification in gastric cancer lung metastasis: Utilizing an overall survival nomogram and comparing it with previous staging

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2024年第2期16卷 357-381页

作者： zhi-ren Chen Mei-Fang Yang zhi-Yuan Xie Pei-An Wang Liang zhang Ze-Hua Huang Yao Luo Department of Science and Education Xuzhou Medical UniversityXuzhou Clinical CollegeXuzhou 221000Jiangsu ProvinceChina Department of Neurology Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina Department of Neurology Clinical LaboratoryGastrointestinal SurgeryCentral Hospital of XuzhouCentral Hospital of XuzhouXuzhou 221000Jiangsu ProvinceChina Department of Public Health Xuzhou Central HospitalXuzhou 221000Jiangsu ProvinceChina Department of Gastroenterology Xuzhou Centre HospitalXuzhou 221000Jiangsu ProvinceChina Department of Public Health Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Gastric cancer(GC)is prevalent and aggressive,especially when patients have distant lung metastases,which often places patients into advanced *** identifying prognostic variables for lung metastasis in GC patients,it may be po-ssible to construct a good prediction model for both overall survival(OS)and the cumulative incidence prediction(CIP)plot of the *** To investigate the predictors of GC with lung metastasis(GCLM)to produce nomograms for OS and generate CIP by using cancer-specific survival(CSS)*** Data from January 2000 to December 2020 involving 1652 patients with GCLM were obtained from the Surveillance,epidemiology,and end results program *** major observational endpoint was OS;hence,patients were se-parated into training and validation *** analysis determined va-rious *** and multivariate Cox analyses validated the independent predictive *** distinction and calibration were performed with the time-dependent area under the curve(AUC)and calibration *** evaluate the accuracy and clinical usefulness of the nomograms,decision curve analysis(DCA)was *** clinical utility of the novel prognostic model was compared to that of the 7th edition of the American Joint Committee on Cancer(AJCC)staging system by utilizing Net Reclassification Improvement(NRI)and Integrated Discrimination Improvement(IDI).Finally,the OS prognostic model and Cox-AJCC risk stratification model modified for the AJCC system were *** For the purpose of creating the OS nomogram,a CIP plot based on CSS was *** multivariate regression analysis identified eleven significant prognostic factors(P0),time-de-pendent ROC curve(training/v

关键词： Gastric cancer Lung metastasis Nomograms Surveillance Epidemiology Surveillance epidemiology and end results program database Overall survival Prognosis

Chinese patients with adult onset leukodystrophy caused by CST3 variants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第7期51卷 778-780页

作者： Yi zhang zhi-Ying Wu Department of Medical Genetics and Center for Rare Diseases Zhejiang Key Laboratory of Rare Diseases for Precision Medicine and Clinical TranslationSecond Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Nanhu Brain-computer Interface Institute HangzhouZhejiang 314050China Department of Neurology Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China MOE Frontier Science Center for Brain Science and Brain-machine Integration School of Brain Science and Brain MedicineZhejiang UniversityHangzhouZhejiang 310012China

Leukodystrophies represent a group of cerebral white matter disorders that mainly affect axon-glia *** disorders are clinically diverse and display significant genetic *** is challenging to differentiate hereditary leukodystrophies,particularly those that present in adulthood,from acquired leukodystrophies and other genetic disorders,such as multiple sclerosis(MS)or hereditary spastic paraplegia(HSP)(Wei et al.,2021).Over the past few decades,a series of causative genes associated with leukodystrophies have been identified(Kohler et al.,2018).Nevertheless,a significant proportion of patients still lack a precise molecular diagnosis.

关键词： al. patients Kohler

Double active sites promoting hydrogen evolution activity and stability of CoRuOH/Co_(2)P by rapid hydrolysis

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7期35卷 206-211页

作者： Bin Dong Ning Yu Qiu-Yue Wang Jing-Ke ren Xin-Yu zhang zhi-Jie zhang Ruo-Yao Fan Da-Peng Liu Yong-Ming Chai State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Cobalt-based phosphides show excellent hydrogen evolution reaction(HER)performance,however,improving the intrinsic activity and stability of it in alkaline electrolyte still remains a ***,CoRuOH/Co_(2)P/CF with heterojunction structure was developed by means of molten salt and rapid hydrolysis(30 s).The OH-from rapid surface hydrolysis of Co_(2)P as a hydrogen adsorption site can facilitate the formation of thin CoRuOH layer as a water dissociation site,which may bring out better synergistic effect for alkaline ***,the covering of CoRuOH can improve the stability of Co_(2)P for *** drives at 100 mA/cm^(2),it only requires overpotential of 81 mV in 1.0 mol/L KOH(25℃).Even at higher current density(1000 mA/cm^(2)),CoRuOH/Co_(2)P/CF can also operate stability for at least 100 *** coupling with NiFe-LDH/IF in a two-electrode system,the voltage of NiFe-LDH/IF(+)||CoRuOH/Co_(2)P/CF(-)at 1000 mA/cm^(2)is merely 1.77 V with 100 h,demonstrating great potential for water *** implementation of this work provides a new strategy and reference for the further improvement of transition metal phosphides as HER electrocatalysts.

关键词： CoRuOH/Co_(2)P/CF Enhanced activity and stability Double active site Large current density Hydrogen evolution reaction

SNR-adaptive deep joint source-channel coding scheme for image semantic transmission with convolutional block attention module

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 1-11页

作者： Yang Yujia Liu Yiming zhang Wenjia zhang zhi State Key Laboratory of Networking and Switch Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

With the development of deep learning(DL),joint source-channel coding(JSCC)solutions for end-to-end transmission have gained a lot of *** deep JSCC schemes support dynamically adjusting the rate according to different channel conditions during transmission,enhancing robustness in dynamic wireless ***,most of the existing adaptive JSCC schemes only consider different channel conditions,ignoring the different feature importance in the image processing and *** uniform compression of different features in the image may result in the compromise of critical image details,particularly in low signal-to-noise ratio(SNR)*** address the above issues,in this paper,a dual attention mechanism is introduced and an SNR-adaptive deep JSCC mechanism with a convolutional block attention module(CBAM)is proposed,in which matrix operations are applied to features in spatial and channel dimensions *** proposed solution concatenates the pooling feature with the SNR level and passes it sequentially through the channel attention network and spatial attention network to obtain the importance evaluation *** show that the proposed solution outperforms other baseline schemes in terms of peak SNR(PSNR)and structural similarity(SSIM),particularly in low SNR scenarios or when dealing with complex image content.

关键词： semantic communication joint source-channel coding image transmission

Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第6期37卷 230-245页

作者： Chang-Kai Wen Wen ren Qing-Zhen Zhu Chun-Jiang Zhao Zhen-Hao Luo Sheng-Li zhang Bin Xie zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent Agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

Typhoon-Induced Ocean Waves and Stokes Drift:A Case Study of Typhoon Mangkhut(2018)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第4期38卷 711-724页

作者： WU zhi-yuan GAO Kai CHEN Jie zhang Hao-jian DENG Bin JIANG Chang-bo LIU Yi-zhuang LYU Zhao YAN ren School of Hydraulic and Environmental Engineering Changsha University of Science&TechnologyChangsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China School of Civil Engineering Hunan University of TechnologyZhuzhou 412007China

Ocean waves and Stokes drift are generated by *** study investigated the characteristics of ocean waves and wave-induced Stokes drift and their effects during Typhoon Mangkhut using European Centre for MediumRange Weather Forecasts(ECMWF)ERA5 datasets and observational *** results revealed that the typhoon generated intense cyclones and huge typhoon waves with a maximum wind speed of 45 m/s,a minimum pressure of955 h Pa,and a maximum significant wave height of 12 *** Stokes drift caused by typhoon waves exceeded 0.6m/s,the Stokes depth scale exceeded 18 m,and the maximum Stokes transport reached 6 m^(2)/*** spatial distribution of 10-m wind speed,typhoon wave height,Stokes drift,Stokes depth,and Stokes transport during the typhoon was highly correlated with the typhoon *** distribution along the typhoon track showed significant zonal asymmetry,with greater intensity on the right side of the typhoon track than on the left *** findings provide important insights into the impact of typhoons on ocean waves and Stokes drift,thus improving our understanding of the interactions between typhoons and the ocean *** study also investigated the contribution of Stokes transport to the total net transport during typhoons using Ekman-Stokes Numbers as a comparative *** results indicated that the ratio of Stokes transport to the total net transport reached up to 50%within the typhoon radius,while it was approximately 30%outside the *** Stokes transport induced by typhoon waves led to divergence in the transport direction,which resulted in upwelling of the lower ocean as a compensation ***,Stokes transport played a crucial role in the vertical mixing of the ocean during *** findings suggested that Stokes transport should be paid more attention to,particularly in high latitude ocean regions,where strong winds can amplify its effects.

关键词： Stokes drift typhoon waves Ekman-Stokes transport vertical mixing Typhoon Mangkhut

A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： zhi Dan WANG Guo Ming zhang School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816P.R.China Frontiers Science Center for Nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2) and certain quasi-orthogonality on a subspace of L^(2),in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2+:={(x,t,λ)∈R^(n+1)×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independent coefficients,and satisfying the De Giorgi/Nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates

Deciphering and integrating invariants for neural operator learning with various physical mechanisms

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第4期11卷 111-122页

作者： Rui zhang Qi Meng zhi-Ming Ma Academy of Mathematics and Systems Science Chinese Academy of Sciences(CAS) Microsoft Research

Neural operators have been explored as surrogate models for simulating physical systems to overcome the limitations of traditional partial differential equation(PDE) solvers. However, most existing operator learning methods assume that the data originate from a single physical mechanism, limiting their applicability and performance in more realistic scenarios. To this end, we propose the physical invariant attention neural operator(PIANO) to decipher and integrate the physical invariants for operator learning from the PDE series with various physical mechanisms. PIANO employs self-supervised learning to extract physical knowledge and attention mechanisms to integrate them into dynamic convolutional *** to existing techniques, PIANO can reduce the relative error by 13.6%–82.2% on PDE forecasting tasks across varying coefficients, forces or boundary conditions. Additionally, varied downstream tasks reveal that the PI embeddings deciphered by PIANO align well with the underlying invariants in the PDE systems, verifying the physical significance of PIANO.

关键词： neural operator PDE solver contrastive learning physical invariants