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41.
Coenzyme Q10 (CoQ10) is a major ingredient in skin care products because of its anti‐wrinkle effects, although it has some side effects especially at higher amounts. In this study, we compare the anti‐wrinkle related properties of CoQ10 and a proprietary Commiphora mukul gum resin (guggul) and triheptanoin preparation (GU‐TC7). GU‐TC7 is prepared with a supercritical CO2‐co‐solvent extraction with ethanol, standardized to 2% guggulsterones and triheptanoin, a triglyceride composed of three 7‐carbon fatty acids. Treatment of CCL‐110 skin fibroblasts with GU‐TC7 demonstrates a mild proliferative effect compared to CoQ10 and increased type I collagen synthesis. Additionally, GU‐TC7 inhibited matrix metalloproteinase‐1 (MMP‐1) expression in a dose‐dependent manner at 20–100 μg mL?1 and inhibited human elastase expression by more than 50% as compared to no elastase inhibition with CoQ10 treatment. These results suggest that GU‐TC7 possesses properties that are applicable to the treatment of wrinkles and may be considered for its further evaluation in skin care products.  相似文献   
42.
张华  张杰  高燕 《纺织学报》2021,42(6):128-132
锦纶/棉混纺织物存在易折皱外观不平整的问题,制约了其在高档服装上的应用。为此,以锦纶/棉混纺织物为研究对象,在坯布预处理后染整前对其进行液氨处理,研究了液氨处理对织物拉伸强力、撕破强力、折皱回复角及表面性能的影响。通过平滑感、温暖感及柔软感3个定量指标,评价液氨处理前后锦/棉混纺织物的风格、手感变化情况。结果表明:液氨整理可以提升锦/棉织物的拉伸强力及撕破强力,处理后织物的折皱回复角从218°提升至252.3°,粗糙度波长与振幅之比从50.46降低至44.87,表明液氨处理后织物的抗皱性和平滑感均得到了明显改善;尽管液氨处理未明显改善织物的柔软感,但处理织物的热导率较未处理织物仍有一定程度降低,致使织物接触温暖感有所提升。  相似文献   
43.
对纯棉织物采用柠檬酸(CA)/丁烷四羧酸(BTCA)/木糖醇免烫整理剂进行免烫整理,探讨柠檬酸质量浓度、丁烷四羧酸质量浓度、木糖醇质量浓度、焙烘时间和焙烘温度对免烫效果的影响,并测试免烫后织物的折皱回复角、白度和强力。结果表明:免烫后织物的折皱回复角与丁烷四羧酸或柠檬酸单独作用于棉织物相当,断裂强力优于两者单独作用。优化免烫整理工艺为:柠檬酸质量浓度60 g/L、丁烷四羧酸质量浓度40 g/L、木糖醇质量浓度17.5 g/L、焙烘温度170℃、焙烘时间3 min。整理后织物的折皱回复角可达267°,白度为54.5,断裂强力为248 N。  相似文献   
44.
The neck is a sun-exposed area. It seems to show the symptoms of photo-ageing as well as facial skin in the elderly. However, the physiological study of neck skin has hardly been reported. We examined the change of skin physiological properties at a neck site with ageing for 61 women (18—69 years old) compared with a cheek site. Water content in stratum corneum (SC) was higher, transepidermal water loss (TEWL) was lower and the turnover rate of SC judged from corneocyte area was slower at the neck site compared with the cheek site. Skin thickness was thinner, skin extensibility and elasticity were higher, skin grooves were deeper, and anisotropy of skin furrows was lower at the neck site than those at the cheek site. It was shown that the neck was also affected by sunlight but not so much as the cheek from the result of gelatinase activity detected in the tape stripped SC. Skin elasticity decreased with ageing at the neck site as well as the cheek site. Fine wrinkles were remarkably increased in the direction of Langer's line with ageing at the neck. Most skin physiological parameters at the neck showed the value between the cheek (heavily sun-exposed area) and back (not sun-exposed area). From these results, it was considered that not only intrinsic ageing but also photo-ageing affected the neck skin. We developed the prototype of cosmetics corresponding to neck skin physiology based on these results, and evaluated the effectiveness of the prototype product by a consumer test including skin measurement for 4 weeks. After treatment, water content increased, and it gave satisfaction in the skin colour brightness, skin elasticity and skin texture improvements for almost all volunteers. It was concluded that the prototype product was useful in neck skin treatment.  相似文献   
45.
Wrinkle recovery behaviour is an important property of fabrics for apparel applications. Fifty fabrics of a variety of constructions have been objectively evaluated in order to study the wrinkle recovery after a deformation. The wrinkle recovery behaviour was studied based on energy modelling. To study their wrinkle recovery properties, fabrics are modelled with the energy method. It is shown that the more the energy dissipation is low, the more fabric is able to recover to its initial state and then the more residual deformation is low. Thus, the energy dissipation can be used to estimate the ability of the fabric to recover to its initial state. In this paper, we also studied the effect of the fatigue test after the repeated wrinkling. Further, the increase of the fatigue cycle number after repeated wrinkling resulted in an increase of the residual deformation and permanent deformation. This method allows us for better approximation of the real behaviour of multidirectional wrinkling of clothing during wearing.  相似文献   
46.
The aim of this study was to compare the artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) models for predicting the wrinkle recovery of polyester/cotton woven fabrics. The prediction models were developed using experimental data-set of 115 fabric samples of different constructions. Warp and weft yarn linear densities, ends/25 mm and picks/25 mm, were used as input/predictor variables, and warp and weft crease recovery angles (CRA) as output/response variables. It was found that the prediction accuracy of the ANN models was slightly better as compared with that of ANFIS models developed in this study. However, the ANFIS models could characterize the relationships between the input and output variables through surface plots, which the ANN models could not. The developed models may be used to optimize the fabric construction parameters for maximizing the wrinkle recovery of polyester/cotton woven fabrics.  相似文献   
47.
In this paper, the wrinkle resistance of plain fabrics woven with weft yarn in S‐ and Z‐twist directions and at various twist levels in different test directions has been measured and then analysed. Results show that the wrinkle resistance increases as the weft yarn twist increases. The wrinkle properties of the fabric show that the direction of test has an obvious effect on the results and the wrinkle resistance depends on the method of folding such as face‐to‐face and back‐to‐back methods. The experimental results showed that there is anisotropy in wrinkle properties of the fabric made of yarns with different twist directions. When the fabric is folded face‐to‐face and the weft twist direction is S, the wrinkle resistance of fabric in various test directions shows a convex curvature, whereas when the same fabric is folded in a back‐to‐back manner then results show a linear curvature. This means that the wrinkle resistance of a fabric differs in various directions and in the method of folding (back‐to‐back or face‐to‐face) and shows an anisotropic wrinkle resistance nature.  相似文献   
48.
为探究较精确、易行的测试和表征织物折皱回复角的方法,首先采用KES-F织物风格仪测试了织物的弯曲、剪切、拉伸和压缩性能,并在KES系统原有力学性能指标基础上引入2个新指标:残余弯曲曲率和残余剪切变形,进而通过数据分析建立了采用织物力学性能指标表示其经、纬向折皱回复角的回归方程;同时分析了织物折皱回复角与各力学性能指标间的相关性.结果表明:回归方程的计算值与折皱回复角的实测值差异不超过0.1°:拉伸功回复率、拉伸比功和弯曲刚度对织物折皱回复性的影响最大,可以通过提高织物的抗拉伸、弯曲和剪切性能及拉伸功回复率来改善织物的抗皱性.  相似文献   
49.
工程中通常采用二次成形技术解决汽车覆盖件中难以一次成形的零件,如门内板、纵梁等,这些零件大多比较复杂,且多为内板。以某车型后门内板为例,研究了该零件局部区域在二次成形过程中的变形特征,采用有限元仿真技术,分析了后门内板在轮毂处易产生局部颈缩和局部起皱的原因。基于有限元仿真平台,系统研究了拉延筋阻力对拉深破裂极限的影响规律,提出并分析了修模方案。通过现场调试生产,结合网格应变技术,验证了分析结果的准确性和修模方案的有效性。  相似文献   
50.
金属薄板成形的数值模拟技术在冲压件生产和模具设计中起着重要的作用。文章以eta/DYNAFORM为实验平台,仿真某油箱上盖板拉深成形中的起皱与破裂现象,在分析起皱、破裂原因和影响因素的基础上,通过压边力与拉深筋的协调配合,较好地解决了上盖板拉深成形中的质量问题。  相似文献   
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