期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
RECOGNITION OF STRUCTURAL DIAGRAM OF MACHINE TOOL SPEED CHANGE SYSTEM WITH ANY COMPOSITE RATIO
1
作者 Zhang Jiwei Shi Zhongde(Northeastern University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第4期339-342,共17页
The speeds of output shaft of a machine tool ni=n1E are expressed by the exponentvalues Ej of series ratio . Based on this expression, the inherert law of differences between expo-nents of driven points from the same ... The speeds of output shaft of a machine tool ni=n1E are expressed by the exponentvalues Ej of series ratio . Based on this expression, the inherert law of differences between expo-nents of driven points from the same drive pair and the same driving point and of correspordingdriving points A method for finding out the exponents of the range ratio hat been given accordingto the law and it is called coordinate diagram method. Finally, a mathematical model is constiuctedand a computer programme is designed. 展开更多
关键词 Structural diagram Unsymmetrical composite ratio Exponent of the range ratio
全文增补中
Experimental research on shear carrying capacity of H-steel concrete composite beam with small shear span ratio 被引量:1
2
作者 王钧 赵天石 +1 位作者 谢恒燕 郑文忠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第3期398-400,共3页
In order to investigate shear carrying capacity of H-steel concrete beam with small shear span ratio,shear test on 5 H-steel concrete composite beams with small span ratio (from 0.7 to 1.1) are reported,including test... In order to investigate shear carrying capacity of H-steel concrete beam with small shear span ratio,shear test on 5 H-steel concrete composite beams with small span ratio (from 0.7 to 1.1) are reported,including test design,test scheme,test method,failure characteristics and test results. Influences of shear span ratio,web of H steel and concrete on shear carrying capacity of this kind of beam are investigated. The main components comprising shear bearing capacity are analyzed. The results show that with the shear span ratio increasing,the contribution of web of H steel and concrete on shear carrying capacity decrease. Based on test data,the calculation formula of shear carrying capacity for this beam is established by curve fitting. 展开更多
关键词 CONCRETE H-steel composite beam shear span ratio shear carrying capacity
下载PDF
Etiological Analysis of 256 Hypouricemia Cases
3
作者 Meilin Lin Rong Lu Yanan Meng 《Proceedings of Anticancer Research》 2024年第3期157-165,共9页
Objective: To analyze the serum uric acid results of patients with hypouricemia hospitalized in the Affiliated Hospital of Hebei University, thereby providing new insights for the prevention and treatment of hypourice... Objective: To analyze the serum uric acid results of patients with hypouricemia hospitalized in the Affiliated Hospital of Hebei University, thereby providing new insights for the prevention and treatment of hypouricemia. Method: This study employed a retrospective case analysis, dividing patients into two groups: 16 cases with uric acid levels less than 50 μmol/L (group Level 1), and 240 cases with uric acid levels between 50 μmol/L and 119 μmol/L (group Level 2). Basic data such as age, gender, department, and clinical diagnosis were collected for each patient. Renal indices, including creatinine, urea, β2-microglobulin, and cystatin C, were analyzed and compared. Results: The highest percentage of patients with uremia was found in Level 1, with a rate of 31.25%. In Level 2, the highest percentage of patients had malignant tumors, with a rate of 15.41%. Tumor sites included the liver, lungs, endometrium, ovaries, breasts, stomach, pancreas, colon, hypopharynx, and others. The second highest percentage was 13.75% for patients with lung diseases, followed by 10% for patients with cranio-cerebral diseases. Other prevalent conditions included renal diseases, hematological diseases, multiple injuries, orthopedic diseases, rheumatological-immunological diseases, and cardiac diseases. There were significant differences between the two uric acid level groups in terms of prevalent diseases (P < 0.05). Additionally, gender differences were significant between the two groups (P < 0.05). However, for renal disease indicators, no significant differences were found between the two levels (P > 0.05). Conclusion: The types of diseases presented by patients were related to different low uric acid levels. Most patients‘ renal function indices were within normal reference ranges at different low uric acid levels. The prevalence of different low uric acid levels was related to gender. 展开更多
关键词 Uric acid HYPOURICEMIA Disease composition ratio
下载PDF
Experimental Study on the Effect of Sediment Composition Ratio on Shallow Water Delta
4
作者 ZENG Can YIN Taiju +1 位作者 SONG Yakai YAN Xiujin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期146-147,共2页
1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subs... 1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subsidence,sediment supply(flow,type),the geometric characteristics of the upstream river,the energy(wave, 展开更多
关键词 Experimental Study on the Effect of Sediment Composition ratio on Shallow Water Delta
下载PDF
Damping of Ni–Mn–Ga epoxy resin composites 被引量:1
5
作者 Wei Liang He Yu +1 位作者 Liu Yufeng Yang Naibin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第6期1596-1605,共10页
By combining the advantages of effcient damping and high mechanical properties,Ni-Mn-Ga particle composites have a very good prospect for applications in damping structure design.In this paper,a ferromagnetic shape me... By combining the advantages of effcient damping and high mechanical properties,Ni-Mn-Ga particle composites have a very good prospect for applications in damping structure design.In this paper,a ferromagnetic shape memory alloy Ni-Mn-Ga composite is prepared.Ni-Mn-Ga particle/bisphenol-A epoxy composite cantilever beam vibration tests under a magnetic feld and without the magnetic feld are conducted to analyze the structural damping ratios n.Meanwhile,the damping characteristics of the Ni-Mn-Ga composite are studied through the axial loading-unloading method and the acoustic emission signals method.The damping coeffcient of the composite for different Ni-Mn-Ga volume fractions is obtained.The interface properties of the composite are discussed by micro examination and axial loading.The relationships between the damping of the composite and that of the component materials are discussed.The specifc damping capacity(SDC)and acoustic emission counts diagram of different specimens with different Ni-Mn-Ga volume fractions are analyzed. 展开更多
关键词 Acoustic emission Ferromagnetic material Material damping Ni-Mn-Ga resin matrix composite Structural damping ratio
原文传递
Composition-dependent micro-structure and photocatalytic performance of g-C_(3)N_(4) quantum dots@SnS2 heterojunction 被引量:5
6
作者 Sheng-Qi Guo Haijun Zhang +4 位作者 Zhenzhong Hu Mengmeng Zhen Bo Yang Boxiong Shen Fan Dong 《Nano Research》 SCIE EI CSCD 2021年第11期4188-4196,共9页
Semiconductor combination is one of the most common strategies to obtain high-efficiency photocatalysts;however, the effect mechanism of composition ratio on micro-structure and photocatalytic activity is remaining un... Semiconductor combination is one of the most common strategies to obtain high-efficiency photocatalysts;however, the effect mechanism of composition ratio on micro-structure and photocatalytic activity is remaining unclear. In this study, a case of g-C_(3)N_(4) quantum dots@SnS_(2) (CNQDn@SnS_(2)) heterojunction with different ratio of CNQD is used to uncover the origin of optimum and excess composition for photocatalysts. Research on the functional mechanism of the optimum composition shows that 0.8 wt.% CNQD are completely attached to the non-(001) facets of SnS_(2), which benefits the formation of type-II heterojunction, resulting in an optimal pollutant degradation and mineralization efficiency. For the excess composition, both experiments and theoretical calculations confirm that excess CNQD (the part exceeding of 0.8 wt.%) located on the (001) facet of SnS_(2), leading to the type-I band alignment of this heterojunction, which severely restricts the separation of photo-induced charge carriers, and thus reduces their lifetime. This work makes the functional mechanism of composition ratio on micro-structure and photocatalytic activity clearer. Related research results provide a new insight into semiconductor combination study and take an important step toward the rational design of highly active photocatalysts. 展开更多
关键词 HETEROJUNCTION semiconductor combination composition ratio PHOTOCATALYST functional mechanism
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部