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101.
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103.
N. Botros M. El-Garhy S. Abdulla H. F. Aly 《Isotopes in environmental and health studies》2013,49(10):368-371
A comparative study on the sorption behaviour of tungsten and rhenium between anion exchange resin, charcoal and alumina and aqueous media of HNO3, HCl and NaCl were carried out. The equilibrium distribution coefficient obtained for the different systems were evaluated and discussed in terms of the separation factor between W and Re. It is found that the systems based on alumina and HCl or NaCl are the most promising systems to be used for development of 188W-188Re generator. The capacity of a chromatographic column loaded with alumina for 188W from 0.01 M HCl, 0.7% NaCl and 1.2% NaCl was found to equals 75.3, 91.0 and 126.0 mg/cm, respectively. A recommended procedure was adopted for 188W-188Re generator. Es wurde eine Vergleichsuntersuchung zum Sorptionsverhalten von W und Re zwischen einem Anionenaustauscherharz einer Aktivkohle und einer Tonerde und den wüβirigen Lösungen von HN03, HCl and NaCl ausgeführt. Die Gleichgeiwichlsverteilungskoeffizienten der unterschiedlichen Systeme wurden bestimmt und als Trennfaktoren zwischen W und Re diskutiert. Es wurde gefunden, daβ sich das System Tonerde/HCl oder NaCl sehr als Trennsystem für die Entuwicklung eines 188W188Re-Generators eignet. Die Kapazitäten einer mit Tonerde gefüllten Säule für 188W mit 0.01 M HCl, 0.7% NaCl und 1.2% NaCl betrugen entsprechend 75.3, 90.0 und 126.0 mg/cm. Es wird eine geeignete Trennmethode für einen 188.188 Re-Generator empfohlen. 相似文献
104.
Li Ma Hui He Can Jiang Ling Zhou Yuanfang Luo Demin Jia 《Journal of Macromolecular Science: Physics》2013,52(11):2232-2244
The preparation and properties of wood–plastic composites (WPCs) based on acrylonitrile–butadiene–styrene (ABS) and bamboo fibers (BFs) are described. The BFs were first modified by alkali treatment in order to improve their adhesion to an ABS matrix. The BF modifications were monitored by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Styrene–maleic anhydride (SMA) copolymer, as a compatibilizer, was added to both the untreated and alkali-treated composites. The changes in the structure and the properties resulting from these treatments were observed by the SEM and mechanical tests. The experimental results indicated that both the alkali treatment of the BF and the inclusion of the SMA copolymer improved the interactions between the BF and ABS matrix, and promoted better mechanical properties of the composites. 相似文献
105.
Summary Extra-fine powdered activated charcoal has been used as stationary phase (coating layer) in solid-phase microextraction (SPME).
The efficiency and reliability of the prepared device have been investigated for the extraction of some volatile organic compounds
such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) from the headspace of water samples. Monitoring of the extracted
compounds and further quantitative analysis of the real samples have been performed by capillary GC-FID. Effects of several
factors such as temperature, addition of salt, and stirring speed on extraction efficiency and exposure time have been studied.
Under optimum conditions, extraction recoveries for these compounds from 50 mL water were >95%. The calibration graphs were
linear in the range 5 to 104 pg mL−1 and the detection limit for each BTEX compound was 1.5–2 pg mL−1. The results obtained by use of this porous layer activated charcoal (PLAC)-coated fiber have also been compared with results
reported in the literature by use of a polydimethylsiloxane (PDMS)-coated fiber.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
106.
采用自组装膜制备技术和超细亚微粒级吸附剂研制高效活性碳多孔层毛细管色谱柱(PLOT),选用K3PO4、K2HPO4和KH2PO4三种不同的磷酸盐对色谱柱进行改性脱活,考察了脱活盐浓度对色谱柱保留行为的影响程度,并采用研制的高效活性碳PLOT毛细管色谱柱对惰性气体和低碳烃(H2、Air、CO、CO2和C1-C4烃)进行了分离分析,结果表明:在高效活性碳PLOT毛细管色谱柱制备工艺中,活性碳吸附剂的最佳粒度为0.5-0.7μm之间;磷酸盐脱活剂的最佳浓度为1.5%,老化时间为250℃;所研制的高效活性碳PLOT毛细管色谱柱对惰性气体和低碳烃具有较好的分离度。 相似文献
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108.
Determination of the rate at which volatile organic molecules diffuse through the wall of a polysiloxane rubber tube, shows that the full depth of the rubber lining of ultra-thick film open tubular traps is utilized for the retention of volatile organic compounds in headspace gas analysis. Small apolar molecules migrate rapidly through the rubber, but larger molecules and polar compounds diffuse relatively slowly into the rubber. Neither traps with a thick film of an apolar stationary phase, nor those with an ultra thick polysiloxane rubber lining retain highly volatile compounds very effectively. Traps containing activated charcoal particles fused into their inside glass surface have a much higher capacity than those with activated charcoal particles embedded in a layer of stationary phase. 相似文献
109.
V. Bonomini S. Stefoni G. Feliciangeli L. Colì M. P. Scolari R. Prandini C. U. Casciani M. Taccone Gallucci A. Albertazzi V. Mioli F. Mastrangelo 《Applied biochemistry and biotechnology》1984,10(1-3):157-166
The use of charcoal hemoperfusion in the treatment of chronic renal failure has been proposed and applied by several authors.
The availability of coating membranes of increased biocompatibility currently allows a safer and wider use of this purifying
technique. It has been recently demonstrated that long-term treatment with combined hemodialysis/hemoperfusion yields an improvement
of certain dialysis-resistant uremic signs in patients on regular dialysis treatment, while in selected patients it affords
a marked reduction (up to one-third) in the overall time of treatment per week. The tolerance of long-term treatment is good.
In line with these findings, a multicenter study has been carried out in Italy with two main aims: (1) to see whether long-term
treatment with charcoal hemoperfusion is really safe and substantially free from side effects; (2) to verify in a larger and
more varied population of patients whether such long-term treatment actually improves certain uremic signs persisting despite
adequate dialysis treatment. A third phase of the multicentric study (reducing the weekly time of treatment) is currently
being worked on. Five nephrology and dialysis departments took part in the study: in Bologna, Rome, Chieti, Ancona, and Lecce. 相似文献
110.
In water and without using any ligand, palladium charcoal-catalyzed Suzuki coupling reaction of tetraarylborates with aryl bromides could be achieved in excellent yield. A concise mechanism consisting of four catalytic cycles is depicted in this paper. 相似文献