检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

论矛盾分析法的发现机制及其科学价值

数学教育学报 2004年第3期13卷 40-42页

作者：顾越岭盐城师范学院数学系江苏盐城224002

矛盾分析法着眼于所论数学问题的矛盾内涵,通过揭露差异,促使差异双方进行矛盾转化,寻求条件与结论间的内在联系,再借助这个联系实现数学解题.矛盾分析法将解题变为一种“程式化”的操作过程.在这个过程中,它的发现机制是“揭露差异—... 详细信息

矛盾分析法着眼于所论数学问题的矛盾内涵,通过揭露差异,促使差异双方进行矛盾转化,寻求条件与结论间的内在联系,再借助这个联系实现数学解题.矛盾分析法将解题变为一种“程式化”的操作过程.在这个过程中,它的发现机制是“揭露差异—矛盾转化—寻求联系”,这个机制有助于做出数学发现,提高解题效率,降低解题难度,其逻辑程序可作为机械化解题的逻辑基础,有助于推进解题机械化的研究.

关键词：数学教学解题方法矛盾分析法机械化解题解题程式化数学发现

Experimental and numerical study of combustion characteristics of ammonia-hydrogen-air swirling flame with/without secondary air injection

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第4期37卷 243-255页

作者： Chunyu LIU Chenhu GAO Yue HUANG Hua JIN Dan ZHAO Wenjiang XU yancheng YOU School of Aerospace Engineering Xiamen UniversityXiamen 361005China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China department of Mechanical Engineering University of CanterburyChristchurch 8041New Zealand

Ammonia (NH_(3)) is currently considered to be a potential carbon-free alternative fuel,and its large-scale use as such would certainly decrease greenhouse gas emissions and meet increasingly stringent emission *** the low flame propagation speed and high NO production of NH_(3) hinder its direct application as a renewable fuel,co-combustion of NH_(3)–H_(2)is an effective way to overcome these *** this study,the combustion characteristics of NH_(3)–H_(2)swirling flames under different equivalence ratios and H_2blending ratios conditions are both numerically and experimentally ***,the One-Dimensional (1D) laminar flame computation presents a comparison base and the Three-Dimensional (3D) numerical simulation yields detailed flame property ***,the high-speed camera takes instantaneous swirl flame images and the gas analyzer measures the NO emission at the exit plane of the flame *** and quantitative analysis is performed on the flame structure and NO emission for a series of NH_(3)–H_(2)swirl *** variation trends of the NO emission calculated using different techniques agree very *** quantitative results show that the NO emissions are much higher at lean equivalence ratios than those at rich equivalence ratios,and such difference is closely related to the combustion flame ***,it is shown that the utilization of secondary air injection can achieve a significant reduction in NO emissions at the exit of the combustion chamber at equivalence ratios less than or equal to 0.9.

关键词： Ammonia combustion Swirling flow NO emission characteristics Secondary combustion Chemical reaction mechanism

Tissue adhesive,ROS scavenging and injectable PRP-based‘plasticine’for promoting cartilage repair

在线全文

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2024年第1期3卷 94-107页

作者： Shiao Li Dawei Niu Haowei Fang yancheng Chen Jinyan Li Kunxi Zhang Jingbo Yin Peiliang Fu department of Orthopedics Shanghai Changzheng HospitalNaval Medical UniversityShanghai 200003P.R.China department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444P.R.China

Platelet-rich plasma(PRP)that has various growth factors has been used clinically in cartilage ***,the short residence time and release time at the injury site limit its therapeutic *** present study fabricated a granular hydrogel that was assembled from gelatin microspheres and tannic acid through their abundant hydrogen *** microspheres with the gelatin concentration of 10wt%and the diameter distribution of 1-10 lm were used to assemble by tannic acid to form the granular hydrogel,which exhibited elasticity under low shear strain,but flowability under higher shear *** viscosity decreased with the increase in shear ***,the granular hydrogel exhibited self-healing feature during rheology ***,granular hydrogel carrying PRP not only exhibited well-performed injectability but also performed like a‘plasticine’that possessed good *** granular hydrogel showed tissue adhesion ability and reactive oxygen species scavenging *** hydrogel carrying PRP transplanted to full-thickness articular cartilage defects could integrate well with native cartilage,resulting in newly formed cartilage articular fully filled in defects and well-integrated with the native cartilage and subchondral *** unique features of the present granular hydrogel,including injectability,plasticity,porous structure,tissue adhesion and reactive oxygen species scavenging provided an ideal PRP carrier toward cartilage tissue engineering.

关键词： cartilage regeneration granular hydrogel gelatin tannic acid PRP

Crosstalk between glioblastoma and tumor microenvironment drives proneural–mesenchymal transition through ligand-receptor interactions

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

Genes & Diseases 2024年第2期11卷 874-889页

作者： yancheng Lai Xiaole Lu Yankai Liao Pei Ouyang Hai Wang Xian Zhang Guanglong Huang Songtao Qi Yaomin Li department of Neurosurgery Institute of Brain DiseaseNanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China Laboratory for Precision Neurosurgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Glioblastoma(GBM)is the most common intrinsic and aggressive primary brain tumor in adults,with a median survival of approximately 15 *** heterogeneity is considered responsible for the treatment resistance and unfavorable ***-mesenchymal transition(PMT)represents GBM malignant progression and recurrence,which might be a breakthrough to understand GBM heterogeneity and overcome treatment *** is a complicated process influenced by crosstalk between GBM and tumor microenvironment,depending on intricate ligand-receptor *** this review,we summarize the autocrine and paracrine pathways in the GBM microenvironment and related ligand-receptor interactions inducing *** also discuss the current therapies targeting the PMT-related autocrine and paracrine ***,this review offers a comprehensive understanding of the failure of GBM-targeted therapy and ideas for future tendencies of GBM treatment.

关键词： Autocrine Glioblastoma Ligand-receptor interaction Microenvironment Paracrine Proneural-mesenchymal transition

Embedding Perovskite in Polymer Matrix Achieved Positive Temperature Response with Inversed Temperature Crystallization

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

Energy & Environmental Materials 2024年第5期7卷 361-371页

作者： Meiting Peng Xue Guan Yingzhu Wu Nan Zhang Qi Feng Liyong Tian yancheng Wu Yangfan Zhang Feng Gan Fuqin Deng Meilin Huang Guichuan Xing Ningbo Yi college of Textile Science and Engineering Wuyi University Institute of Applied Physics and Materials Engineering University of Macau School of Applied Physics and Materials Wuyi University Faculty of Intelligent Manufacturing Wuyi University

Organic perovskites are promising semiconductor materials for advanced photoelectric applications. Their fluorescence typically shows a negative temperature coefficient due to bandgap change and structural instability. In this study, a novel perovskite-based composite with positive sensitivity to temperature was designed and obtained based on its inverse temperature crystallization, demonstrating good flexibility and solution processability. The supercritical drying method was used to address the limitations of annealing drying in preparing high-performance perovskite. Optimizing the precursor composition proved to be an effective approach for achieving high fluorescence and structural integrity in the perovskite material. This perovskite-based composite exhibited a positive temperature sensitivity of28.563%℃-1for intensity change and excellent temperature cycling reversibility in the range of 25–40℃in an ambient environment. This made it suitable for use as a smart window with rapid response. Furthermore, the perovskite composite was found to offer temperature-sensing photoluminescence and flexible processability due to its components of perovskite-based compounds and polyethylene oxide. The organic precursor solvent could be a promising candidate for use as ink to print or write on various substrates for optoelectronic devices responding to temperature.

关键词： flexibility inversed temperature crystallization perovskite positive temperature response

The Green formula and heredity of algebras

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china mathematics 2005年第5期48卷 610-617页

作者： ZHANG Guanglian & WANG Shuai department of Mathematical Sciences, Tsinghua University, Beijing 100084, china yancheng teachers college, yancheng 224002, china department of mathematics, Johns Hopkins University, Baltimore, MD21218, U.S.A. department of Mathematical Sciences Tsinghua University Beijing China yancheng teachers college Yancheng China department of mathematics Johns Hopkins University Baltimore USA

Let A be a finite dimensional algebra over a field k with q elements. It is shown that the Green formula is true in mod-A if and only if A is a hereditary algebra.

关键词： Green formula idempotent ideal hereditary algebra.