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31.
The Tilemsi phosphate rock (TPR) of Mali is a good and cheaper alternative to imported phosphate fertilizers. Many soil microorganisms
can also mobilize sparingly soluble inorganic phosphates, and several have a good potential to improve plant growth. With
the aim of improving the response of wheat cultivated in Mali to fertilization with TPR, in this work we describe the isolation
and selection from four different Malian soils of TPR-solubilizing microorganisms (TSM) with high P-mobilization activities.
When the rhizosphere of three wheat cultivars (Alkama Beri, Hindi Tossom and Tetra) was used to isolate TSM, only bacterial
isolates were selected. TPR-solubilizing fungi were only obtained by soil enrichment in liquid medium containing TPR as sole
P source. In the rhizosphere a significant correlation was observed between the total microbial population and the number
of microorganisms solubilizing TPR. No such correlation was observed in the rhizoplane. Initially 44 bacteria and 18 fungi
were selected, but after 10 subcultures on agar plates and a liquid medium, only 6 bacteria and 2 fungi retained their high
P solubilizing trait. A field inoculation trial was established during the growing season 2000–2001 in Koygour. Wheat cv.
Tetra was inoculated with the 8 selected TSM (6 bacteria and 2 fungi) and fertilized with 30 kg ha−1 P added as TPR or diammonium phosphate. The growth parameters measured were plant height at 30 and 60 days, the number of
leaves per main stem at 60 days, and root and shoot dry matter yields 60 days after planting. Root colonization by indigenous
arbuscular mycorrhizas (AM) was also measured in 45 day-old plants. Significant interactions were observed between TSM inoculation
and P-fertilization for root colonization with AM, plant height at 30 days and root dry matter yield. The bacterial isolate
Pseudomonas sp. BR2, which appeared to be a mycorrhiza helper bacterium, significantly enhanced wheat seedling emergence very early (5 days
after planting) under field condition, and caused 128% increase in root dry matter yield. The two TPR-solubilizing fungal
isolates Aspergillus awamori Nakazawa C1 and Penicillium chrysogenum Thom C13 also caused respectively 60 and 44% increases in root dry matter yields. The choice of the TSM BR2, C1 and C13 for
further field trials is discussed.
This article was previously published in Nutrient Cycling in Agroecosystems Volume 72/2 pages 147–157. The online version
of the original article can be found at . 相似文献
32.
Integrative Extraction of Ergosterol, (1→3)-α-D-Glucan and Chitosan from Penicillium chrysogenum Mycelia 下载免费PDF全文
Abstract Ergosterol,(1→3)-α-D-glucan and chitosan are important biomaterials. In this research, a process has been developed to integratively extract ergosterol, (1→3)-α-D-glucan, and chitosan from Penicillium chrysongenum mycelium. First the mycelia are pretreated with 0.1mol·L^-1 of NaOH. After recovery by centrifugation the solid portion is made to undergo saponification and deacetylation reactaons by addition of 2mol·L^-1 NaOH and et anol.After reaction, extraction is carried out by addition of petroleum ether, which separates the reaction mixture into two phases. The upper layer of petroleum ether contains extracted ergosterol, and the .bottom layer of NaOH solution contains (1→3)-α-DEglucan; the chitosan is on the mycelia residuum. After isolation, the recovery yield of ergosterol is 0.52% of dry mycelium. That of (1→3)-α-D-glucan is about 8.2%; and chitosan is 5.7% with 86% deacetylation. The compositions have been characterized by 1R, HPLC analyses. 相似文献
33.
壳聚糖酶的分离提纯及其酶学性质研究 总被引:1,自引:0,他引:1
从土壤中筛选获得的高产壳聚糖酶菌株Penicillium sp.ZD-Z1,经发酵、分离提取出两种壳聚糖酶A和酶B,并对它们分别进行酶学性质测试.分别测定酶A和酶B的等电点、相对分子质量、最适反应温度和pH、不同脱乙酰度的壳聚糖对酶活的影响.并考察了两种壳聚糖酶的酶解方式,结果表明,酶A为内切酶,酶B为外切酶. 相似文献
34.
35.
Barkai Hassan El Abed Soumya Sadiki Moulay Iraqui Houssaini Mohammed 《The Journal of Adhesion》2016,92(5):341-348
The sessile drop technique was used to investigate the evolution of the physicochemical properties of cedar wood as a function of contact time with the Penicillium expansum spores. The most important finding showed that the impact of different contact periods (2, 4, 6, 8, 10, and 24 hr) on the wood surface were very indicative. In fact, after 2 hr of contact, the results have shown a significant impact of the bioadhesion of spores to the substrate on both the hydrophobic character (θW = 108.5°; ΔGiwi = ?28.25 mJ/m2), the electron donor (γ? = 13.63 mJ/m2), and the electron acceptor (γ+ = 4.35 mJ/m2) parameters that were significantly reduced compared to the initial wood (θW = 118.5°; ΔGiwi = ?6.29 mJ/m2; γ? = 32.1 mJ/m2; and γ+ = 9.1 mJ/m2). In addition, this decrease of parameters continued over time to stabilize after 10 hr of contact. Indeed, after 24 hr, the acid/base properties were almost zero and the contact angle with water decreased to 30°. Moreover, it was found that the coefficient of correlation (r2) was strong between the contact angle with water, the surface energy, and the electron acceptor character with the contact time parameter with values (r2 = 0.65), (r2 = 0.79), and (r2 = 0.68), respectively. 相似文献
36.
Akihiko Sakurai Tatsuhiko Yamamoto Akemi Makabe Shinichi Kinoshita Mikio Sakakibara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(1):9-14
The screening of a strain which could perform lignin removal was carried out. Based on taxonomic study the isolated strain (LM‐2) was identified as Penicillium sp. LM‐2 could decolorize 0.6 g dm?3 lignin within 4 days in a shaking culture at 25 °C. The efficiency of decolorization of the lignin was over 80% in the pH range of 4.0–6.0, but was low above pH 6.2. The rise of temperature had a slight adverse effect on the lignin decolorization in the range of 25–35 °C. Lignolytic enzymes such as lignin peroxidase, manganese peroxidase and laccase were not detected in the culture broth or within the fungal cells. The lignin was removed from the high molecular weight fraction mainly by adsorption and accumulation inside the cells. © 2001 Society of Chemical Industry 相似文献
37.
Qin‐Tao Liu Malcolm R Clench Judith L Kinderlerer 《Journal of the science of food and agriculture》2002,82(5):553-558
Structural isomers of monoacylglycerols (monoglycerides, MAGs) were identified and compared after degradation of butter oil by two strains of Penicillium roquefortii and a commercial lipase from P roquefortii (EC 3.1.1.3) at pH 7.0 and 10 °C. The conditions were selected as they were comparable with those used in the manufacture of blue mould‐ripened cheese. The commercial lipase was selected to compare with the fungal strains in terms of acyl migration. Results showed that the main isomers formed by lipolysis with the commercial lipase were sn‐2 MAGs (64 mol%), whilst spores and emerging mycelia of P roquefortii produced mainly sn‐1(3) MAGs (83–90 mol%). The work reported here may lead to further assessment of different MAG structural isomers as natural preservatives in foods and dairy products. © 2002 Society of Chemical Industry 相似文献
38.
The Penicillium genus of fungi is a frequently reported cause of allergic reactions. However, only a limited number of allergens have been reported. In Penicillium spp., many allergens show higher IgE-binding activity in culture filtrate extracts than in cellular extracts. In order to investigate the IgE-reactive profile of mold-sensitized patients, secreted IgE-reactive proteins from Penicillium citrinum were identified by 2-DE, serum immunoblotting, and nanoLC-MS/MS. Among the IgE-reactive spots, one known allergen, Pen c 13, and four novel allergens were identified. The cDNAs coding for Pen c 32 and Pen c 30 were cloned using designed primers based on nanoLC-MS/MS analysis. The amino acid sequences of Pen c 32 and Pen c 30 were, respectively, found to have extensive similarity with those of pectate lyases and catalases from various fungi. Native Pen c 30 was shown to have catalase activity and to bind to serum IgE from 48% of mold-allergic patients and induced immediate type skin reactions in a sensitized patient. Here, we present a proteome approach which resulted in the identification of four novel secreted allergens. These novel allergens might be useful in allergy diagnosis and in the treatment of mold-allergic disorders. 相似文献
39.
Visible moulds were isolated and identified from traditional Greek sausages from Northern Greece. Penicillium species were isolated from 90.8% of visibly mouldy sausages. Penicillium solitum, P. nalgiovense and P. commune species made up 60.6% of the total number of isolates. The most frequently occurring species was P. solitum (26.1%). P. nalgiovense and P. olsonii were found to be positive to penicillin production in an agar assay and further examination for antibiotic production in liquid culture with complex media designed for penicillin production, confirmed their ability for penicillin biosynthesis. Penicillin production by P. olsonii is reported for the first time in this study. 相似文献
40.
浙江工学院固定化细胞有机酸发酵科研组 《浙江工业大学学报》1991,(1)
本文从85株霉菌中,筛选得到了六株青霉属D-异抗坏血酸(EA)产生菌,其中点青霉2553产酸能力较高.通过UV、DES或~(60)Coγ-射线对其单孢子进行诱变处理,并进行随机筛选和理性化筛选,获得一最高正变株,其产酸水平达14.47mg/ml,较出发菌株提高50%. 相似文献