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1.
目的评价氩激光联合活血散瘀中药治疗视网膜分支静脉阻塞的临床疗效。方法氩激光联合活血散瘀中药治疗组40眼和单纯氩激光治疗组30眼,随访6~12月,观察视力、视网膜出血和黄斑水肿变化并行统计分析。结果联合中药治疗组患者和单纯氩激光光凝组治疗前后视力均有显著差异(P<0.05),治疗后两组最后视力比较差异显著(P<0.05),前者较后者视力进步明显。而且联合中药治疗出血吸收情况明显优于前组(P<0.05),并且两组黄斑水肿发生率治疗前后均有显著差异(P<0.05),虽然治疗6月后两组黄斑水肿发生率无显著差异(P>0.05),但后者较前者发生率低。结论氩激光光凝联合活血散瘀中药治疗更能促使视网膜分支静脉阻塞患者的出血吸收、黄斑水肿减轻及视功能的改善,在总体上取得了更好的治疗效果。 相似文献
2.
用扫描电子显微镜观测研究了室温下195keVAr+辐照非晶态合金Co(60)Fe(12)Ni(10)Si6B(12)和Fe(39)Ni(39)V2Si(12)B8在各剂量阶段的表面损伤形貌。结果表明,表面损伤是发泡和溅射相互竞争的过程。低剂量下,表面损伤以发泡为主;而在高剂量时,表面发泡消失,溅射造成的多孔粗糙表面损伤结构形成。对高剂量时表面发泡消失的可能机制作了探讨。 相似文献
3.
《Ceramics International》2019,45(11):14347-14353
To optimize the process and obtain highly conducting and transparent Aluminum-doped zinc oxide (AZO) thin films, AZO films were deposited on glass substrates at room temperature by Radio-frequency (RF) magnetron sputtering with various Argon flow rates. The influences of Argon flow rate on structure, morphology, optical, electrical and photoluminescence properties of AZO films were investigated by varying the Argon flow rate from 36 to 68 sccm. The best quality AZO film with resistivity 1.39 × 10−3 Ω cm, sheet resistance 8.2 Ω/sq and 84.2% average visible transmittance was prepared at 44 sccm for 30 min. Also, the self-heating effect of target was investigated by preparing AZO films for 10 min and 20 min at 44 sccm, 180 W and 1.0 Pa. The influence of increasing structural quality actually affected by Argon flow rate was more prominent on carrier concentration than mobility. The schematic illustration of microstructural evolution was proposed. The average growth rate of around 60 nm/min demonstrated the self-heating effect of target was weak and could be ignored. 相似文献
4.
介绍了WMZ1 31 5型管子管板全位置数控脉冲氩弧焊机在换热器的管子与管板接头焊接中的应用 ,对手工氩弧焊和自动管板焊接进行了对比分析讨论 相似文献
5.
Chung-Hao Chiang Hsiu-Hsien Su Ying-Chien Fang Sheng-Yuan Chu 《Ceramics International》2018,44(6):6278-6284
In this paper, Ca6BaP4O17:Sm3+ and Li+ co-doped Ca6BaP4O17:Sm3+ phosphors were synthesized in air and argon atmospheres using a solid-state reaction method. The phosphor morphologies and crystal structure were studied using scanning electron microscopy and X-ray diffraction, respectively. The emission and absorption characteristics were investigated using photoluminescence emission spectroscopy and diffuse reflectance spectroscopy. The surface states and composition of phosphor were investigated using X-ray photoelectron spectroscopy. The emission integrated intensities of the phosphors sintered in an argon atmosphere increased 3.5 fold than the ones sintered in air atmosphere, with Li+ ions becoming embedded in the lattice of the Ca6BaP4O17:Sm3+ phosphor. This occurs because there are fewer defect/oxygen vacancies and less of the secondary phase forms, leading to better Sm3+ emission. The results suggest that sintering a mixture of the raw materials of a phosphor in an argon atmosphere is a good approach for synthesizing Ca6BaP4O17:Sm3+ phosphor powders. The color purity and CIE values of an optimized phosphor sample sintered in an argon atmosphere with an Li+ ion compensator were calculated to be ~ 99.6% and (0.612,0.386) in the orange–red region under 405-nm excitation, respectively. Moreover, the solid solubility of Sm3+ ions in the Ca6BaP4O17 host can be enhanced by using an argon atmosphere in the synthesis process. 相似文献
6.
《Journal of Adhesion Science and Technology》2013,27(10-11):1313-1323
Abstract The present study was undertaken to investigate the effect of argon plasma treatment on the extent of Foley catheter surface modification. Foley catheter (flexible tube made of silicone rubber, used for urinary catheterization) surface was treated at different argon (Ar) RF plasma powers. The surface modification was assessed by measurement of contact angle. Contact angle study shows decrease in contact angle and increase in surface free energy shows more polar group incorporation at low power plasma treatment. Atomic force microscopy (AFM) revealed an increased average surface roughness proportional to plasma power. Optical emission spectroscopy (OES) shows various states of argon causing surface modification. 相似文献
7.
Thomas J. Manning 《臭氧:科学与工程》2000,22(1):53-64
The catalytic role of using inert gases to increase the efficiency and lower the power cost of producing ozone (O3) from high purity oxygen (O2) in a process incorporating an electrical discharge is demonstrated. Three inert gases (Ar, Ne, He) and N2 are individually mixed with O2 and the results presented. The increase in ozone production is partially attributed to the increase in electron density provided by the ionization of the inert gas in the discharge. 相似文献
8.
9.
The corrosion behavior of an austenitic stainless steel (UNS S30400) has been characterized in a 10,000 h test conducted in hydrogenated, ammoniated water at 260 °C. The corrosion kinetics were observed to be parabolic, the parabolic rate constant being determined by chemical descaling to be 1.16 mg dm−2 h−1/2. X-ray photoelectron spectroscopy, in combination with argon ion milling and target factor analysis, was applied to provide an independent estimate of the rate constant that agreed with the gravimetric result. Based on the distribution of the three oxidized alloying constituents (Fe, Cr, Ni) with respect to depth and elemental state, it was found that: (a) corrosion occurs in a non-selective manner, and (b) the corrosion film consists of two spinel oxide layers--a ferrite-based outer layer (Ni0.2Fe0.8)(Fe0.95Cr0.05)2O4 on top of a chromite-based inner layer (Ni0.2Fe0.8)(Cr0.7Fe0.3)2O4. These compositions agree closely with the solvi phases created by immiscibility in the Fe3O4-FeCr2O4 binary, implying that immiscibility plays an important role in the phase separation process. 相似文献
10.