全文获取类型
收费全文 | 110篇 |
免费 | 3篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 1篇 |
综合类 | 7篇 |
化学工业 | 41篇 |
金属工艺 | 1篇 |
机械仪表 | 5篇 |
建筑科学 | 6篇 |
矿业工程 | 3篇 |
能源动力 | 1篇 |
轻工业 | 32篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 1篇 |
一般工业技术 | 2篇 |
冶金工业 | 3篇 |
自动化技术 | 11篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 3篇 |
2013年 | 9篇 |
2012年 | 5篇 |
2011年 | 3篇 |
2010年 | 4篇 |
2009年 | 13篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有117条查询结果,搜索用时 15 毫秒
21.
开发全自动鞋底磨边机取代手工鞋底磨边,对鞋底磨边机进行了总体布局设计.根据磨鞋加工的特点,设计出了适合鞋底磨边的整体机械结构,完成了各子系统设计,并完成了数控系统的选型.成功开发出了全自动鞋底磨边机. 相似文献
22.
在大型水电站建设过程中,业主常面临一些独家议标施工项目的合同谈判工作。针对该类项目合同谈判的特点,结合实践中遇到问题和切身体会,从合同谈判的准备工作、谈判重点和需注意的问题等方面加以讨论。 相似文献
23.
采用新型聚醚多元醇为原料,制备出具有较好机械性能的微孔聚氨酯弹性体鞋底制品,并对影响其制品性能的主要因素进行了探讨。结果发现,三官能度聚醚及接枝聚合物聚醚多元醇的适量引入,可显著改善鞋底制品的物理机械性能。 相似文献
24.
T. Tsuka R. Nishimura M. Hishinuma Y. Murahata M. Yamashita K. Azuma T. Osaki N. Ito Y. Okamoto T. Imagawa 《Journal of dairy science》2019,102(11):10105-10118
The goal of the present study was to determine the effect of sole horn thickness (SHT) and sole horn hardness (SHD) on ultrasonographic visualization of sole structures in the inner and outer claws of 150 Holstein-Friesian cows, and to evaluate different ultrasound frequencies for this purpose. Ultrasonographic views of the sole structure were considered complete when 3 echogenic lines, representing the ventral surface of the sole horn, the borders of the sole horn and soft-tissue layer, and the ventral surface of the distal phalanx, were seen. The proportion of complete ultrasonographic views of the sole structures, designated as the ultrasonographic visualization proportion (UVP), and the measurement errors of SHT were evaluated by comparing images from computed tomography (CT) and ultrasonography. The latter images were generated using 3 different probes, frequencies of 6.5 and 5.0 MHz, and 2 different ultrasound machines (#1 and #2) to assess the apex, middle, and heel regions of the claws. The UVP were 60.8 to 77.9% for the 6.5-MHz probe in ultrasound machine #1 (probe A), which were lower than those (>90%) for both the 5.0-MHz probe in ultrasound machine #1 (probe B) and the 5.0-MHz probe in ultrasound machine #2 (probe C). The UVP was significantly lower in claws with an SHD ≥50 units than in claws with an SHD <40 or 40 to <50 units (UVP: 77.1% compared with 93.7 and 91.4%, respectively) when measured with probe B. In claws with an SHT <10 mm, the UVP was significantly lower when SHD was ≥50 units compared with <40 or 40 to >50 units; the values were 69.0% versus 91.3 and 85.9%, respectively, for probe A, and 89.7% versus 100 and 100%, respectively, for probe B. When SHT were measured by either probes A or B in ultrasound machine #1, the proportions of claws in which ultrasonographic values were within a ±1 mm range compared with the values obtained by CT were 84.9 to 91.3% for CT-determined SHT <5 mm, 66.7 to 71.9% for CT-determined SHT 5 to <7 mm, 28.9 to 51.2% for CT-determined SHT 7 to <10 mm, and 6.2 to 19.7% for CT-determined SHT ≥10 mm. The data indicated that increased SHT was associated with a decrease in ultrasonographic measurement accuracy. In claws with an SHT <5 mm, the high proportion of ultrasonographic values that were accurate within a ±1 mm range suggests that this imaging modality would be useful in cows with thin soles. 相似文献
25.
介绍EVA/NBR/NR三元共混胶在耐油环境中使用的微孔鞋底的配方、工艺及主要性能。本产品具有橡胶与塑料的综合性能,有良好的耐油性、轻便、柔软、耐屈挠、尺寸稳定性好的特点。 相似文献
26.
研究了采用高聚合度聚氯乙烯(HPVC)与丁腈橡胶(NBR)并用制造透明鞋底的过程,讨论了材料折光率、稳定剂、HPVC/NBR并用比、补强剂和硫化体系等因素对鞋底的透明性和力学性能的影响。实验结果表明:选择共混比HPVC/NBR=70/30(质量比)、TS_3白炭黑30份、超细CaCO_3 3~5份及适量助剂.可制得透明性和力学性能较好的耐油透明鞋底;含铅类稳定剂不能在硫黄硫化的HPVC/NBR透明鞋底中使用;硫化体系对透明鞋底的力学性能影响不大。 相似文献
27.
28.
研究分析了聚氨酯(PU)鞋底生产过程中影响产品质量的主要因素。实践证明:多元醇组分(A液)与异氰酸酯组分(B液)的配比是生产中的关键。准确掌握原液质量,严格控制生产温度,尽量维持系统内压力恒定,以确保A、B液配比在一定范围内,才能生产出合格的聚氨酯鞋底。 相似文献
29.
T.J.R. Fernandes R.C. Alves T. Souza J.M.G. Silva M. Castro-Cunha L.M.P. Valente M.B.P.P. Oliveira 《Food chemistry》2012
A growth trial with Senegalese Sole (Solea senegalensis Kaup, 1858) juveniles fed with diets containing increasing replacement levels of fishmeal by mixtures of plant protein sources was conducted over 12 weeks. Total fat contents of muscle, liver, viscera, skin, fins and head tissues were determined, as well as fatty acid profiles of muscle and liver (GC-FID analysis). Liver was the preferential local for fat deposition (5.5–10.8% of fat) followed by fins (3.4–6.7% fat). Increasing levels of plant protein in the diets seems to be related to increased levels of total lipids in the liver. Sole muscle is lean (2.4–4.0% fat), with total lipids being similar among treatments. Liver fatty acid profile varied significantly among treatments. Plant protein diets induced increased levels of C16:1 and C18:2 n−6 and a decrease in ARA and EPA levels. Muscle fatty acid profile also evidenced increasing levels of C18:2 n−6, while ARA and DHA remained similar among treatments. Substitution of fishmeal by plant protein is hence possible without major differences on the lipid content and fatty acid profile of the main edible portion of the fish – the muscle. 相似文献
30.
The aim of this study was to examine changes in RNA expression for growth factors, cytokines, and receptors in epidermal-dermal tissues of the bovine claw relative to host age, claw segment, and disease state of the horn. Epidermal-dermal tissues were collected from the coronary, wall, sole, and bulb segments of 8- to 9-mo-old Holstein fetuses, normal adult cows, and adult cows with sole ulceration. Anatomic and pathologic characteristics were determined in tissues stained with eosin and hematoxylin, and RNA expression levels were evaluated using real-time, quantitative PCR. In normal tissues, certain RNA expression levels were clearly affected by host age: 290.0-, 610.0-, 53.4-, and 8.1-fold greater expression of granulocyte-macrophage colony stimulating factor was observed in fetal coronary, wall, sole, and bulb segment relative to adult tissues, respectively. A claw segment effect was also observed in that IL-1α expression was greater (1.59-fold) in the normal adult wall relative to the coronary segment, and IL-18 expression was greater (16.2-fold) in the normal adult sole compared with the coronary segment and 2.88 greater in the fetal sole relative to the bulb segment. Sole ulceration was associated with hemorrhage, thrombosis, inflammation, and striking increases in IL-1β, IL-18, and inducible nitric oxide synthase, and with less dramatic, albeit measurable, changes in IL-1 type I receptor, IL-1 receptor antagonist, and tumor necrosis factor-α. Amidst striking increases in keratinocyte growth factor receptor (i.e., 21.0-fold, 10.4-fold, 0, and 21.6-fold in the coronary, wall, sole, and bulb segments, respectively), a concomitant decrease occurred in keratinocyte growth factor (i.e., 0.80-, 0.54-, 0.56-, and 0.72-fold, respectively). The results demonstrated changes in disease state and, to a lesser extent, claw segment and were accompanied by alterations in the RNA expression of several cytokines, growth factors, and receptors present in the normal claw. 相似文献