全文获取类型
收费全文 | 112篇 |
免费 | 6篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 41篇 |
金属工艺 | 4篇 |
机械仪表 | 8篇 |
建筑科学 | 1篇 |
能源动力 | 10篇 |
轻工业 | 11篇 |
水利工程 | 2篇 |
无线电 | 9篇 |
一般工业技术 | 24篇 |
冶金工业 | 2篇 |
自动化技术 | 7篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 1篇 |
2014年 | 6篇 |
2013年 | 4篇 |
2012年 | 2篇 |
2011年 | 8篇 |
2010年 | 8篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 5篇 |
2006年 | 11篇 |
2005年 | 12篇 |
2004年 | 6篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1982年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有119条查询结果,搜索用时 31 毫秒
91.
Six novel polyureas were prepared from benzimidazolin‐2‐one and benzimidazolin‐2‐thione, which acted as hard segments, with two aromatic diisocyanates (4,4′‐diphenylmethane diisocyanate and toluene 2,4‐diisocyanate) and one aliphatic diisocyanate (hexamethylene diisocyanate). The polymers that formed were fully characterized with Fourier transform infrared spectroscopy, 13C‐NMR cross‐polarization/magic‐angle spinning, differential scanning calorimetry, and thermogravimetry. X‐ray diffraction revealed that the polymers contained crystalline and amorphous regions that varied with the nature of the backbone structures. All the polyureas were insoluble in common organic solvents, and this made it difficult to investigate their solution properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 576–583, 2006 相似文献
92.
Amala Muniandy Choy Sin Lee Wen Huei Lim Mallikarjuna Rao Pichika Kit Kay Mak 《应用聚合物科学杂志》2021,138(13):50126
Polymer carrier with biodegradable, biocompatible as well as solubility enhancing properties are highly looked upon in the pharmaceutical industry to improve the drug delivery systems. A series of hyperbranched poly(glycerol esteramide) (HPGEA) with Mw of 5000–12,000 Da, degree of branching of 57%–62%, and hydroxyl values of 200–280 mg KOH/g sample were synthesized through polycondensation of N,N-bis(2-hydroxyethyl)stearamide (diethanolamide) and poly(glycerol ester) (PGE). The HPGEAs were characterized by ATR-FTIR, GPC, 1H and 13C-NMR, and DSC. The enthalpy of fusion of HPGEAs (43–84 J g−1) were lower than the commercial polymers (193–391 J g−1), indicating its potential as drug carrier for solid dispersion (SD). HPGEA-based SDs showed substantial enhancement in solubility and release rate than pure drug, commercial polymer-based SDs, as well as commercial formulation. The safety of HPGEAs and HPGEA-based SDs were proven through MTT assay with IC50 of 2400–9800 and 1200–3500 μg ml−1, respectively. 相似文献
93.
This paper presents a study on the quality of interference fringes formed from a pulsed UV (255 nm, 5.6 kHz, and 40 ns) source for an application in writing fiber Bragg gratings (FBGs). The interference fringes of separation of about 8 microm, formed by a biprism of apex angle 2 degrees , were studied for their contrast, evolution of contrast, and positional and intensity stability over a period of 5 min (over 10(6) pulses). Second harmonic UV (255 nm) sources of different spatial coherence and pointing stability characteristics were employed as the inputs. It is established that the UV fringes contrast and interference pattern stability with time is largely controlled by the optical resonator geometry of the fundamental wavelength (510 nm) copper vapor laser (CVL) oscillator. In particular, the generalized diffraction filtered resonator (GDFR) CVL produced the highest quality second harmonic beam with the highest fringes contrast and stability. The implications of these results were studied by employing these UV sources for the fabrication of the C-band FBGs by a 24 degrees apex angle biprism. 相似文献
94.
K. Mallikarjuna Reddy V. Ramesh Babu K. S. V. Krishna Rao M. C. S. Subha K. Chowdoji Rao M. Sairam T. M. Aminabhavi 《应用聚合物科学杂志》2008,107(5):2820-2829
Semi‐interpenetrating network (IPN) of sodium alginate (NaAlg) and N‐isopropylacrylamide (NIPAAm) microspheres were prepared by water‐in‐oil (w/o) emulsification method. The microspheres were encapsulated with 5‐fluorouracil (5‐FU) and release patterns carried in 7.4 pH at temperatures of 25 and 37°C. The semi‐IPN microspheres were characterized by Fourier transform infrared spectroscopy (FTIR). Differential scanning calorimetry (DSC) and scanning electron microscopic studies were done on the drug‐loaded microspheres to confirm the polymorphism of 5‐FU and surface morphology of microspheres. These results indicated the molecular level dispersion of 5‐FU in the semi‐IPN microspheres. Particle size and size distribution were studied by laser light diffraction technique. Microspheres exhibited release of 5‐FU up to 12 h. The swelling studies were carried in 1.2 and 7.4 pH buffer media at 25 and 37°C. Drug release from NaAlg‐NIPAAm semi‐IPN microspheres at 25 and 37°C confirmed the thermosensitive nature by in vitro dissolution. The micro domains have released in a controlled manner due the presence of NIPAAm in the matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
95.
R. Hari Ganesh V. Subramanian V. Balasubramanian J.M. Mallikarjuna A. Ramesh R.P. Sharma 《Renewable Energy》2008,33(6):1324-1333
In this work, a single cylinder conventional spark ignition engine was converted to operate with hydrogen using the timed manifold fuel injection technique. A solenoid operated gas injector was used to inject hydrogen into the inlet manifold at the specified time. A dedicated electronic circuit developed for this work was used to control the injection timing and duration. The spark timing was set to minimum advance for best torque (MBT). The engine was operated at the wide-open throttle condition. For comparison of results, the same engine was also run on gasoline.The performance and emission characteristics with hydrogen and gasoline are compared. From the results, it is found that there is a reduction of about 20% in the peak power output of the engine when operating with hydrogen. The brake thermal efficiency with hydrogen is about 2% greater than that of gasoline. A lean limit equivalence ratio of about 0.3 could be attained with hydrogen as compared to 0.83 with gasoline. CO, CO2 and HC emissions were negligible with hydrogen operation. However, for hydrogen operation, NOx emission was four times higher than that of gasoline at full load power. The best ignition timing for hydrogen was much retarded when compared to gasoline. The effect of hydrogen injection pressure was also studied and no specific changes were observed. The effect of operating speed was also studied. 相似文献
96.
Li‐Wen Hu Namratha Gurram Michael S. Bloom Zhengmin Qian Steven W. Howard Juilet Iwelunmor Mohammed Zeeshan Shao Lin Bo‐Yi Yang Xiao‐Wen Zeng Kang‐Kang Liu Qian‐Sheng Hu Guang‐Hui Dong 《Indoor air》2019,29(3):477-486
We conducted a cross‐sectional study to investigate the associations between recent home renovation exposure and lung function in children. We randomly recruited 7326 school children residing in 24 districts from seven cities in northeastern China. We collected information about home renovations from parents using a questionnaire and lung function measurements from children using spirometer recordings gathered by trained professionals and expressed as the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), maximal mid‐expiratory flow (MMEF), and peak expiratory flow (PEF). We identified higher odds of diminished lung function among these with home renovation in the previous 2 years compared to those without home renovation in the previous 2 years, for FVC (odds ratios [ORs] = 1.84 [95%CI: 1.58, 2.15]; FEV1: ORs = 2.82 [95%CI: 2.36, 3.36]; PEF: ORs = 1.51 [95%CI: 1.24, 1.83]; and MMEF: ORs = 1.90 [95%CI: 1.60, 2.24]). The associations were stronger among children exposed to new polyvinyl chloride (PVC) flooring compared to children exposed to other surface materials. Our results were consistent throughout the analysis of each type of renovation materials. In conclusion, recent home renovation exposure was associated with poor lung function among children. Strategies to protect home owners and their families from respiratory hazards during and after renovation are required. 相似文献
97.
Shilpa M Naik Anitha K Raman Minnuru Nagamallika Challa Venkateshwarlu Suresh Prasad Singh Santosh Kumar Shravan Kumar Singh Tomizuddin Ahmed Sankar Prasad Das Krishna Prasad Tajwar Izhar Nimmai P Mandal Nitendra Kumar Singh Shailesh Yadav Russell Reinke Ballagere Prabhu Mallikarjuna Swamy Parminder Virk Arvind Kumar 《Journal of the science of food and agriculture》2020,100(11):4150-4164
98.
99.
Protective effect of dietary ginger on antioxidant enzymes and oxidative damage in experimental diabetic rat tissues 总被引:1,自引:0,他引:1
Kondeti Ramudu Shanmugam Korivi Mallikarjuna Kesireddy Nishanth Chia Hua Kuo Kesireddy Sathyavelu Reddy 《Food chemistry》2011
The role of oxidative stress has been reported in various diabetic complications. This study was undertaken to evaluate the protective effect of ginger, a medicinal plant, on the tissue antioxidant defence system and lipid peroxidative status in streptozotocin-induced diabetic rats. An increased reactive oxygen species and insufficient antioxidant activity are associated with diabetes mellitus, which is mainly responsible for diabetic pathogenesis. The role of ginger as antioxidant markers of liver and kidney were investigated. The antioxidant effect of the ginger was compared with glibenclamide, a well-known hypoglycaemic drug. The diabetic rats exhibited lower activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) and reduced glutathione (GSH) content and higher level of malondialdehyde (MDA) in hepatic and renal tissues as compared with normal rats. The activities of all parameters were found to be increased, except MDA in ginger-treated diabetic rats, in hepatic and renal tissues. Ginger supplementation, for 30 days to diabetic rats, resulted in significant dose-dependent hypoglycaemic and antioxidant activities. These findings suggest that ginger treatment exerts a therapeutic protective effect in diabetes by decreasing oxidative stress, and hepatic and renal damage. 相似文献
100.
A higher-order shear deformable C° continuous finite element is developed and employed to investigate the transient response of isotropic, orthotropic and layered anisotropic composite plates. The governing ordinary linear differential equations are integrated using the central difference explicit time integration scheme. A special mass matrix diagonalization scheme is adopted which conserves the total mass of the element and includes the effects due to rotary inertia terms. Numerical results for deflections and stresses are presented for rectangular plates under various boundary conditions and loadings. The parametric effects of the time step, finite element mesh, lamination scheme and orthotropy on the transient response are investigated. The numerical results are compared with those available in the literature, and with the results obtained by solving the same problems using the Mindlin plate element. 相似文献