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31.
考察了自制的三种高纯度双直链烷基硫酸盐型孪连表面活性剂的界面性能和驱油性能。结果表明,双直链烷基硫酸盐型孪连表面活性剂的CMC在10-5~10-6mol/L之间;随着表面活性剂浓度的增加,界面张力达到平衡时所需要的时间明显延长;随着联接基团碳链长度的增加,油水界面张力先增大再减小;此类孪连表面活性剂具有非常好的抗一价盐二价盐的能力;用2C13-C2-2C2SO4Na作为驱油剂进行驱油实验时,可以使采收率在水驱基础上提高5%以上,具有比较好的驱油效果。 相似文献
32.
以废弃棉为原料在微波辐照下制得羧甲基纤维素,通过测定其取代度得出最佳反应条件为:m(纤维素):m(NaOH):m(C1CH2COOH)=1.0:1.1:1.2,以95%的乙醇为分散介质,碱化间歇辐射时间2min,醚化间歇辐射时间2min,微波辐射功率为200W。所得产品为白色粉末,取代度为0.75。 相似文献
33.
以交联羧甲基纤维素技术开发了适合番茄酱特性的增稠剂,并对其应用效果进行了研究。建立了羧甲基纤维素交联反应试验:先将羧甲基纤维素溶于乙醇溶液,再添加氢氧化钠后于35℃水浴加热,间歇添加10%环氧氯丙烷乙醇溶液,待反应终止。优化试验结果表明:交联反应使用20g联羧甲基纤维素-8时,氢氧化钠用量2g、环氧氯丙烷4mL、温度35℃、乙醇75%、反应时间8h条件下,制得的交联羧甲基纤维素增稠效果比较适合番茄酱。通过对瓜尔豆胶、黄原胶、卡拉胶、番茄纤维、大豆纤维等几种常用番茄酱增稠剂的增稠效果(颜色、黏手性等)对比,说明本试验开发的交联羧甲基纤维素更适合番茄酱增稠,并保持了番茄酱原有的组织状态特征特征。 相似文献
34.
《Drug development and industrial pharmacy》2013,39(10):1235-1244
Aim: Investigated the self-assembly and characterization of novel antifouling polyethylene glycol (PEG)-coated iron oxide nanoparticles as nanoprobes for magnetic resonance imaging (MRI) contrast agent. Method: Monodisperse oleic acid-coated superparamagnetic iron oxide cores are synthesized by thermal decomposition of iron oleate. The self-assembly behavior between iron oxide cores and PEG-lipid conjugates in water and their characteristics are confirmed by transmission electron microscope, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. Result: Dynamic light scattering shows superparamagnetic iron oxide nanoparticles coated with PEG are stable in water for pH of 3–10 and ionic strengths up to 0.3 M NaCl, and are protein resistant in physiological conditions. Additionally, in vitro MRI study demonstrates the efficient magnetic resonance imaging contrast characteristics of the iron oxide nanoparticles. Conclusion: The result indicates that the novel antifouling PEG-coated superparamagnetic iron oxide nanoparticles could potentially be used in a wide range of applications such as biotechnology, MRI, and magnetic fluid hyperthermia. 相似文献
35.
《Drug development and industrial pharmacy》2013,39(9):939-958
AbstractTolmetin microspheres were prepared by the coacervation process from the ethylcellulose. Microspheres were obtained both in presence and without protecting colloids, such as polyisobutilene (PIB) or ethyl-vinylacetate copolimers (EVA). The effect of these agents on the preparation, drug content, wall thickness, surface morphology, drug dissolution arid release from microspheres, were evaluated. The dissolution rate analysis was carried out also in the presence of a surfactant (Tween 80) at different pH values.In addition, microspheres containing Tolmetin as a core material were submitted to biological tests, in comparison with the free drug, to evaluate upon experimental models the antipyretic activity and the gastric tolerability. 相似文献
36.
Carlos A. Alzate Carlos F. Valdés Arturo Berrio Javier De La Cruz Carlos A. Londoño 《Fuel》2009,88(3):437-529
A pelletization process was designed which produces cylindrical pellets ∼8 mm in length and 4 mm in diameter. These ones were manufactured using a blend of Pinus Patula and Cypress sawdust and coal in proportions of 0%, 5%, 10%, 20%, and 30% v/v of coal of rank sub-bituminous extracted from the Nechí mine (Amagá-Antioquia). For this procedure, sodium carboxymethyl cellulose (CMC) was used as binder at three different concentrations. The co-gasification experiments were carried out with two kinds of mixtures, the first one was composed of granular coal and pellets of 100% wood and the second one was composed of pulverized wood and granular coal pellets. All samples were co-gasified with steam by using an electrical heated fluidized-bed reactor, operating in batches, at 850 °C. The main components of the gaseous product were H2, CO, CO2, CH4, and N2 with approximate quantities of 59%, 6.0%, 20%, 5.0%, and 9.0% v/v, respectively, and the higher heating values ranged from between 7.1 and 9.5 MJ/Nm3. 相似文献
37.
《IEEJ Transactions on Electrical and Electronic Engineering》2017,12(5):728-735
The highly random manner in which veins spread along a finger, their immunity to counterfeiting, active liveness, and user friendliness make finger veins the best choice for a biometric identification system (BIS). In this paper, veins of six fingers of two hands of a person are used to develop a secure, reliable, and robust multimodal BIS (MBIS). The main structure of the proposed MBIS is based on the effective combination of rank‐ and decision‐level fusion. In the training step, the power (weight) of each single modality is estimated by extracting the information that lies in the cumulative match characteristic (CMC) curve. The testing step consists of two main parts. In the first part, the region of the finger vein is extracted by using a simple method, and then the binarized statistical image features (BSIFs) algorithm is used to extract feature vectors. In the second part, final decision for the test input probe is made by generating ‘top rank‐decision matrix ’, which fuses the information of each biometric identifier in the hybrid rank‐decision level. The obtained results show that proposed method is more reliable and accurate than other fusion techniques at the post‐classification fusion level. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
38.
连续式超临界水中煤/CMC催化气化制氢 总被引:6,自引:0,他引:6
在向水煤浆中添加CMC(羧甲基纤维素钠),成功实现水煤浆高压均匀输送基础上,对超临界水中煤/CMC催化气化制氢性能进行了进一步研究。结果表明:在压力20~25MPa、停留时间15~30s、NaOH添加量0.1%、反应器外壁温650℃条件下,超临界水中煤/CMC催化气化制氢气体产物中H2摩尔含量远比常规气化高,主要气体产物是H2、CO2和CH4。增加物料中CMC的含量、升高压力均有利于提高气体产物中心的产量,延长停留时间虽有利于物料气化但不利于氢气的制取。 相似文献
39.
A novel surfactant and hydrotrope, sodium diisopropylnaphthalene sulfonate (SDIPNS) has been developed. It contains about
92% diisopropylnaphthalene sulfonate, compared to other materials which are less than 50% diisopropylnaphthalene sulfonate.
Aqueous solutions of 34–36% active SDIPNS have dual functionality. They have excellent surface properties and are compatible
with conventional anionic, nonionic, and amphoteric surfactants. They demonstrate good laundering detergency in combination
with sodium lauryl ethoxy sulfate, with or without builder. They maintain surface activity in 150 ppm hard water (Ca2+/Mg2+=2∶1), 5% NaCl, pH 2, and pH 12. They are effective hydrotropes. They enhance surfactant solubility, raise the cloud point
of nonionic surfactants, and modify the viscosity of surfactant formulations. They are light in color and are low-foaming.
Presented as a Poster Session at the American Oil Chemists' Society Annual Meeting, May 9–12, 1999, Orlando, Florida. 相似文献
40.
采用羧甲基纤维素(CMC)对聚酰胺多胺环氧氯丙烷(PAE)树脂进行改性,以期在保持原有增湿强作用不变的前提下,提高PAE树脂的使用性能,并赋予其一定的增强性能,降低PAE树脂的使用成本。探讨了PAE树脂的改性工艺,并对改性PAE树脂进行傅里叶红外光谱表征,研究了改性PAE树脂对纸张的增强效果及对浆料Zeta电位、滤水性能的影响。结果表明,在PAE树脂成品中引入9%的CMC为最优改性工艺;在此工艺条件下制备的改性PAE树脂用量为0.6%时,浆料的滤水性能最优;在相同用量下(0.6%),与传统PAE树脂相比,添加改性PAE树脂所抄纸张的抗张指数提高约22%,湿抗张指数提高约19%,耐折度提高约13%,撕裂指数提高约5%,内结合强度提高约6%。 相似文献