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81.
Geunseon Park Hyun-Ouk Kim Jong-Woo Lim Chaewon Park Minjoo Yeom Daesub Song Seungjoo Haam 《Nano Research》2022,(3):2254-2262
A recurrent pandemic with unpredictable viral nature has implied the need for a rapid diagnostic technology to facilitate timely and appropriate countermeasures... 相似文献
82.
Eung Sup Lee Jae Yeon Park Sung Ho Yeom Young Je Yoo 《Korean Journal of Chemical Engineering》2008,25(1):139-143
For effective toluene degradation, the effects of a nitrogen source were studied with Pseudomonas putida BZ912, which was isolated from crude oil contaminated soil and is capable of degrading VOC. Two nitrogen sources, ammonia
and nitrate, showed different effects on specific growth rates (0.25 hr−1 and 0.12 hr−1, respectively), biomass yields (0.56 vs. 0.39) and specific toluene degradation rates (0.51 hr−1 vs. 0.26 hr−1). Under the resting cell conditions, the cells pre-cultured in the ammonia-containing medium showed higher specific toluene
degradation rate than that in nitrate-containing medium (0.045 hr−1 vs. 0.038 hr−1). Ammonia as a nitrogen source was effective for degradation in high toluene concentration because high cellular biomass
was accomplished. Nitrate showed slow growth rate compared to ammonia. The resting cell conditions demonstrated that it was
able to degrade toluene efficiently without increasing biomass. These conditions could be a solution for degrading VOC after
high cellular biomass was obtained in a biofilter. By changing the nitrogen source and the growth conditions according to
the toluene concentration, the control of cell biomass and the desired removal capacity were accomplished. 相似文献
83.
Won-Kyu Han Seok-Jun Hong Chong-Seung Yoon Seung-Jin Yeom Sung-Goon Kang 《Microelectronic Engineering》2009,86(3):374-378
We have developed a novel activation technique for the conformal electroless deposition (ELD) of Cu on a SiO2 substrate modified with an organic self-assembled monolayer. The SiO2 substrate was modified with amine groups using 3-aminopropyltriethoxysilane and Au nanoparticles (AuNPs) to form a uniform, continuous catalyst for ELD. The Au catalytic layer formed on the amine-SiO2 substrate was stabilized by electrostatic interactions between the positively charged protonated-amine self-assembled monolayer (SAM) and negatively charged AuNPs. Cu films were then electrolessly deposited on Au-catalyzed SiO2 substrates. The Cu seed layer formed by this method showed a highly conformal and continuous structure. Cu electrodeposition on the 60-nm trench was demonstrated using an acid cupric sulfate electrolyte containing chloride, polyethylene glycol 4000 and bis(3-sulfopropyl)disulfide. The resulting electroplated Cu showed excellent filling capability and no voids or other defects were observed in a 60-nm trench pattern. 相似文献
84.
Myung SW Yeom YH Jang YM Choi HS Cho D 《Journal of materials science. Materials in medicine》2005,16(8):745-751
We successfully introduced peroxide groups onto the surface of PU(Polyurethane) foam(10 PPI) through one atmospheric pressure plasma treatment and sequentially grafted PAAc(poly(acrylic acid)) on the surface of PU through radical copolymerization. The plasma treatment can generate large amount of peroxides on the surface of PU foam and the peroxide groups act as initiators for further grafting of PAAc in the monomer solution. To introduce large amount of peroxides on the surface of PU foam, we studied the effect of plasma rf-power and treatment time on the maximum grafting of PAAc. Through this study, we found that the optimum plasma treatment condition was the rf-power of 100 W and the treatment time of 100 s. On the other hand, we also studied the effect of graft reaction conditions such as temperature, monomer concentration and reaction time on the change of grafting degree (GD). The GD increased with increasing temperature and increased with reaction time before it leveled off at 3 h after reaction started. At low concentration of AAc, the GD was very low but it showed a maximum at the monomer concentration between 60 and 70%. The surface of the modified PU foam was qualitatively and quantitatively analyzed through the use of FT-IR and weight measurement, respectively. We also observed the surface change before and after plasma induced graft co-polymerization through photo and SEM analysis. Finally, we confirmed that the PU foams grafted with PAAc successfully immobilized lysozyme and other proteins from hen egg white. 相似文献
85.
86.
The present study was aimed to treat the dairy wastewater by using anaerobic and solar photocatalytic oxidation methods. The anaerobic treatment was carried out in a laboratory scale hybrid upflow anaerobic sludge blanket reactor (HUASB) with a working volume of 5.9 L. It was operated at organic loading rate (OLR) varying from 8 to 20 kg COD/m3 day for a period of 110 days. The maximum loading rate of the anaerobic reactor was found to be 19.2 kg COD/m3 day and the corresponding chemical oxygen demand (COD) removal at this OLR was 84%. The anaerobically treated wastewater at an OLR of 19.2 kg COD/m3 day was subjected to secondary solar photocatalytic oxidation treatment. The optimum pH and catalyst loading for the solar photochemical oxidation was found to be 5 and 300 mg/L, respectively. The secondary solar photocatalytic oxidation using TiO2 removed 62% of the COD from primary anaerobic treatment. Integration of anaerobic and solar photocatalytic treatment resulted in 95% removal of COD from the dairy wastewater. The findings suggest that anaerobic treatment followed by solar photo catalytic oxidation would be a promising alternative for the treatment of dairy wastewater. 相似文献
87.
During the enzymatic production of biodiesel, methanol has a major inhibitory effect on enzyme activity whereas glycerol has
a minor effect. Revitalization of the methanol-deactivated enzyme or pre-incubation of enzyme with various chemicals turned
out to be unsuccessful. The stepwise feeding of methanol, a widely used conventional method for preventing methanol inhibition,
was optimized in terms of the aliquot number and feeding interval to obtain a high conversion rate as well as a high degree
of final biodiesel conversion. The use of six feedings of methanol with an equivalent molar ratio of 0.75 at 3-h intervals
was found to be the optimal mode for preventing methanol inhibition; a biodiesel conversion rate of approximately 95% could
be achieved within 20 h by using this method. Finally, to prevent contact between the undissolved methanol and the enzyme,
methanol was pre-dissolved in water or biodiesel and fed to the mixture of soybean oil and the enzyme. This pre-dissolution
method completely prevented enzyme inhibition, and a final biodiesel conversion rate of 82.3% was obtained. 相似文献
88.
Host Cell Mimic Polymersomes for Rapid Detection of Highly Pathogenic Influenza Virus via a Viral Fusion and Cell Entry Mechanism 下载免费PDF全文
Woonsung Na Minjoo Yeom Jihye Choi Jihye Kim Jong‐Woo Lim Dayeon Yun Haejin Chun Geunseon Park Chaewon Park Jeong‐Ki Kim Dae Gwin Jeong Van Phan Le Kwangyeol Lee Jae Myun Lee Hyoung Hwa Jeong Daesub Song Seungjoo Haam 《Advanced functional materials》2018,28(34)
Highly pathogenic avian influenza virus (HPAIV) infections have occurred continuously and crossed the species barrier to humans, leading to fatalities. A polymerase chain reaction based molecular test is currently the most sensitive diagnostic tool for HPAIV; however, the results must be analyzed in centralized diagnosis systems by a trained individual. This requirement leads to delays in quarantine and isolation. To control the spread of HPAIV, rapid and accurate diagnostics suitable for field testing are needed, and the tests must facilitate a differential diagnosis between HPAIV and low pathogenic avian influenza virus (LPAIV), which undergo cleavage specifically by trypsin‐ or furin‐like proteases, respectively. In this study, a differential avian influenza virus rapid test kit is developed and evaluated in vitro and using clinical specimens from HPAIV H5N1‐infected animals. It is demonstrated that this rapid test kit provides highly sensitive and specific detection of HPAIV and LPAIV and is thus a useful field diagnostic tool for H5N1 HPAIV outbreaks and for rapid quarantine control of the disease. 相似文献
89.
In this study, thin films of Ag deposited onto glass substrates were etched using inductively coupled fluorine-based plasmas. The effects of various process conditions on the Ag etch characteristics were evaluated to ascertain whether it would be possible to etch patterned Ag films with high etch rates and smooth sidewalls free of involatile etch products. It was found that involatile etch products remained on the substrate when films were etched in CF4-based gas mixtures possessing either O2 or N2 as an additive. However, when Ar was added to either NF3 or CF4, a residue-free etch was obtained provided the partial pressure of Ar was no less than 50%. It is proposed that the residue-free Ag etch mechanism involves the formation of silver fluoride, which is physically sputtered by Ar+ ions. A Ag etch rate of 160 nm/min with a Ag to photoresist etch selectivity exceeding 1.1 was achieved with an inductive power of 1500 W, a d.c. bias voltage of −180 V and a chamber pressure of 0.8 Pa with 50-50 CF4/Ar partial pressures obtained with 60 sccm CF4/60 sccm Ar flows. In addition, these conditions produced smooth Ag sidewall etch profiles. 相似文献
90.
The central effect of 3-morpholinosydnonimine, a nitric oxide donor, on the sympatho-adrenomedullary system was investigated in urethane-anesthetized rats. Intracerebroventricular administration of 3-morpholinosydnonimine (100, 250 and 500 microg/animal) induced a marked elevation of adrenaline levels and a slight elevation of noradrenaline levels in the plasma. These 3-morpholinosydnonimine (250 microg/animal)-induced elevations of catecholamines were abolished by intracerebroventricular treatments with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl 3-oxide (750 microg/animal), a nitric oxide scavenger, and indomethacin (500 microg/animal), a cyclo-oxygenase inhibitor, but not with superoxide dismutase (250 units/animal), a superoxide anion scavenger. Furthermore, the 3-morpholinosydnonimine (250 microg/animal)-induced elevation of plasma adrenaline levels was abolished by intracerebroventricular treatments with thromboxane A2 synthase inhibitors [furegrelate (100, 250 and 1000 microg/animal) and carboxyheptyl imidazole (500 microg/animal)], and also with thromboxane A2 receptor blockers [(+)-S-145 (100, 250 and 1000microg/animal) and SQ29548 (8microg/animal)]. The elevation of noradrenaline levels was, however, not attenuated by these thromboxane A2-related test agents. The present results indicate that nitric oxide but not peroxynitrite markedly activates central adrenomedullary outflow. Thromboxane A2 in the brain is probably involved in this central activation of adrenomedullary outflow. 相似文献