全文获取类型
收费全文 | 57篇 |
免费 | 1篇 |
专业分类
化学工业 | 5篇 |
机械仪表 | 7篇 |
建筑科学 | 2篇 |
能源动力 | 1篇 |
轻工业 | 31篇 |
无线电 | 1篇 |
一般工业技术 | 4篇 |
冶金工业 | 1篇 |
自动化技术 | 6篇 |
出版年
2021年 | 1篇 |
2019年 | 1篇 |
2017年 | 1篇 |
2015年 | 1篇 |
2013年 | 10篇 |
2012年 | 2篇 |
2011年 | 2篇 |
2009年 | 3篇 |
2008年 | 2篇 |
2006年 | 2篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1983年 | 1篇 |
1981年 | 3篇 |
1979年 | 2篇 |
1975年 | 1篇 |
1971年 | 1篇 |
1967年 | 1篇 |
1963年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有58条查询结果,搜索用时 31 毫秒
11.
A numerical method for the optimal design of thin anisotropic laminates is presented, layer thicknesses and lamination angles being the design variables. An optimal solution is pursued with respect to frequency domain objectives, e.g. fundamental frequency and Euler critical load. A special feature of the method is the semi-analytical second order design sensitivity that is computed with the aid of a Rayleigh-Ritz analysis approach. A modified sequential quadratic programming scheme is then introduced, where standard quasi-Newton approximations are avoided by an exact calculation of the Hessian matrix. Furthermore, the robustness of the method with respect to scatter in material properties such as mass density and elastic moduli is assessed. A stochastic extension of the Rayleigh-Ritz approach is developed on this purpose that allows the location of those regions in the design space that are most sensitive to physical parameter randomness. This allows the use of a modified objective function that penalizes sensitive solution. 相似文献
12.
SENSORY QUALITY OF GALA APPLES AS INFLUENCED BY CONTROLLED AND REGULAR ATMOSPHERE STORAGE 总被引:2,自引:0,他引:2
TERRI D. BOYLSTON EUGENE M. KUPFERMAN JOI D. FOSS CLAUDIA BUERING 《Journal of food quality》1994,17(6):477-494
The sensory quality of Gala apples stored for up to 4 months in delayed controlled atmosphere (CA), regular atmosphere (RA), and a combination of sequential CA and RA storage (CR) was evaluated. Sensory analysis included difference and acceptance testing. Firmness, soluble solids and titratable acidity contents, and volatile flavor profiles were measured analytically. Acceptability decreased with storage time. Apples stored in RA were more acceptable than apples stored in CA or CR; the differences between storage treatment were not significant after 4 months of storage. Firmness decreased with storage time, but was not affected by storage treatment. Soluble solids and titratable acidity contents were not affected by storage treatment or time. Storage treatment, storage time, and lot had a significant effect on the volatile flavor profiles. CA storage and extended storage contributed to decreases in the content of volatile flavor compounds. 相似文献
13.
TARSILA MARIA DA SILVA MORAES CLAUDIA FRANCA BARROS SEBASTIÃO JOSÉ DA SILVA NETO VALDIRENE MOREIRA GOMES MAURA DA CUNHA 《Biocell》2009,33(3):155-165
Simira is a predominantly woody Neotropical genus comprising 41 taxa, 16 of which occur in Brazil and eight of them in the southeastern region of Brazil. Leaf blades of Simira eliezeriana Peixoto, S. glaziovii (K. Schum.) Steyerm., S. grazielae Peixoto, S. pikia (K. Schum.) Steyerm., S. rubra (Mart.) Steyerm., S. sampaioana (Standl.) Steyerm. were collected in the southeastern region of Brazil and fixed according to usual methods for light and electron microscopy. The leaf blades show typical characteristics of the Rubiaceae family as dorsiventral mesophyll and paracytic stomata. The presence of two bundle sheaths that extend to the upper epidermal layer, prismatic crystal and crystal-sand, alkaloids in the mesophyll and the organization micromorphological of the outer periclinal wall are considered characteristics representative for the genus. This study also demonstrates some leaf blade characteristics that can be used to Simira species identification (leaf surface, domatia types, epicuticular wax types and patterns of epidermis anticlinal cell walls). 相似文献
14.
This paper presents UAPÉ—a computational environment for modeling and designing environmental geographic applications. UAPÉ is aimed at end-users who are experts in their application domain, but who do not have adequate background in software engineering or database design, and thus are unable to take full advantage of available GIS tools. Its goal is to reduce the impedance between the end-users view of the world and its implementation in Geographic Information Systems. The environment has been designed and implemented so that it can be considered as an auxiliary layer to be coupled to a GIS. The major features of this layer are: it has an open architecture, being independent of a specific GIS, so that it can be coupled to different systems; it allows the user to deal only with the conceptual view of the geographic reality, abstracting the implementation details; it supports a geographic application design methodology, fully integrated with a high-level semantic data model, so there is no impedance mismatch between application design and data modeling. 相似文献
15.
THEODORE R. BECK 《Chemical Engineering Communications》2013,200(1-6):9-16
Recently determined electrical conductivities of anodic AgCl, A1C13, TiBr4, and MgCl2 films are compared to well established conductivities of anodic Ta2O5; and A12O3. All of these films exhibit high-field barrier layer condition. The exponential constant, β. is about the same value for the salts as for oxides but the preexponential constants and conductivities are orders of magnitude larger for the salts. The salts, AlCl3, TiBr4, and MgCl2, in addition, have a series ohmic resistance which is attributed to an outer, continuously-forming and dissolving, hydrated salt layer. 相似文献
16.
17.
18.
Frozen sprats (Sprattus sprattus sprattus) were thawed and separated into three lots: two lots were wrapped and kept chilled in a refrigerator at 4C, one wrapped in aluminum foil (AF), the other in cling film (CF) and a third lot left unpackaged and held in melting ice. Biochemical tests, performed at intervals over a 16‐day period, showed better quality and an extension of shelf‐life for sprats stored unpackaged in ice compared with those held at 4C packed in AF or CF. The levels of trimethylamine oxide‐nitrogen (TMAO‐N) decreased throughout storage and significant differences (P<0.05) were observed between the lot in ice and the lots stored in AF or CF (P<0.05). However, significant differences (P<0.05) were not observed between AF and CF lots during the experiment. Increases in total volatile base nitrogen (TVB‐N) and trimethylamine‐nitrogen (TMA‐N) were significantly retarded, as were reductions in sensory quality, in the ice‐stored fish compared with packaged, refrigerated fish. 相似文献
19.
20.
CAMILLA VARMING TOVE KJÆR BECK MIKAEL AGERLIN PETERSEN YLVA ARDÖ 《International Journal of Dairy Technology》2011,64(2):197-206
Changes in the composition of volatile compounds during processing of cheese powders, made from Emmental and Danbo cheese were analysed by dynamic headspace gas chromatography–mass spectrometry. Samples comprised cheese, melted cheese slurry, the slurry heat treated using three different time and temperature combinations, and the spray‐dried cheese powder. About 100 volatile compounds were identified. During melting of the cheese the level of some volatile compounds increased significantly; heat treatment mainly leads to a loss of compounds and spray drying leads to a substantial reduction of volatile compounds, with the exception of a range of aldehydes that increased. The final cheese powders could, however, be distinguished according to cheese type. 相似文献