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101.
102.
Sabina Smoleń Dominika J. Walaszek Maksymilian Karczewski Emil Martin Dorota Gryko 《Israel journal of chemistry》2016,56(2-3):156-168
The pathogenesis of the cardiovascular system is often associated with dysfunction of soluble guanylate cyclase (sGC), which can be stimulated in both an NO-dependent and -independent manner. It was previously reported that PPIX and its amphiphilic derivatives markedly activate the enzyme. To date, all porphyrins studied are naturally occurring compounds or their derivatives, possessing substituents at β-positions. Such porphyrins are of limited abundance and their derivatives or analogues are difficult to synthesize, while synthetic meso-substituted porphyrins are easy to prepare. Thus, we have decided to study their effect on guanylate cyclase. To this end, a series of trans-AB-porphyrins, bearing both hydrophilic and hydrophobic groups at the opposite ends of the macrocycle, loosely mimicking the arrangement of the substituents in PPIX, was design and synthesized. Their synthesis involves preparation of suitable building blocks – dipyrromethanes, starting from aldehydes or acetals and following an acid-catalyzed [2+2]-dipyrromethane condensation. Biological properties of synthesized porphyrins with regard to sGC activation were tested. meso-Substituted porphyrins do interact with sGC, though they are poor activators, indicating that further optimization of their structure is required. 相似文献
103.
The formation of biogenic amines by fermentation organisms 总被引:6,自引:0,他引:6
Bernhard W. Straub Martin Kicherer Sabina M. Schilcher Walter P. Hammes 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(1):79-82
A total of 523 strains representing 35 species related to food fermentation organisms of practical importance were investigated for their potential for formation of biogenic amines (BA). The investigation was performed with resting cells in phosphate buffer (pH 5.5) and the formation of the following BAs was followed: putrescine, cadaverine, histamine, tyramine and 2-phenylethylamine. No potential was observed in species ofLactococcus, Leuconostoc, Pediococcus, Streptococcus and severalLactobacillus spp., such asL. pentosus andL. sake. A remarkable potential to form BA was observed in strains of carnobacteria,Lactobacillus buchneri, L. curvatus, L. reuteri, Staphylococcus carnosus and, to a lesser extent, inL. alimentarius, L. brevis, L. bavaricus, L. delbrueckii ssp.lactis, Micrococcus spp. andS. piscifermentans. In well known species with a practical function in the fermentation of dairy products, wine or cabbage a potential was observed for few strains only. In view of their role as starters in food fermentation, or their potential use in protective cultures and as probiotics, BA formation by the organisms has to be taken into consideration by selecting appropriate strains.
Die Bildung von biogenen Aminen durch Fermentationsorganismen
Zusammenfassung Das Potential zur Bildung von biogenen Aminen (BA) wurde bei 523 Stämmen, die 35 Spezies aus dem Verwandtschaftsbereich der Lebensmittelfermentationsorganismen zugehörten, untersucht. Zu diesem Zweck wurden ruhende Zellen in Phosphatpuffer (pH 5,5) verwendet und die Bildung der folgenden BA verfolgt: Putrescin, Cadaverin, Histamin, Tyramin, 2-Phenylethylamin. Bei Spezies der GeneraLactococcus, Leuconostoc, Pediococcus, Streptococcus und einigenLactobacillus spp., darunterL. pentosus undL. sake fehlte dieses Potential. Eine deutliche Bildung von BA wurde bei Stämmen von Carnobakterien,Lactobacillus buchneri, L. curvatus, L. reuten undStaphylococcus carnosus beobachtet. Weniger ausgeprägt war die Aminbildung beiLactobacillus alimentarius, L. brevis, L. bavaricus, L. delbrueckii ssp.lactis, Micrococcus spp. undStaphylococcus piscifermentans. Ein Potential bei Spezies, die bei der Fermentation von Milch, Wein und Sauerkraut bekanntermaßen erwünscht sind, wurde nur bei wenigen Stämmen gefunden. In Anbetracht der Bedeutung bestimmter Spezies als Starterkulturen bei Lebensmittelfermentationen und der möglichen Anwendung als Schutzkulturen oder Probiotika ist die mögliche Bildung von BA durch Auswahl geeigneter Stämme ausreichend zu berücksichtigen.相似文献
104.
Theoretical computations have been carried out on ridge acoustic surface waves using the finite-element method. The results obtained agree substantially with experiments performed previously. 相似文献
105.
Niels Hadrup Vadim Zhernovkov Nicklas Raun Jacobsen Carola Voss Maximilian Strunz Meshal Ansari Herbert B. Schiller Sabina Halappanavar Sarah S. Poulsen Boris Kholodenko Tobias Stoeger Anne Thoustrup Saber Ulla Vogel 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(21)
Inhaled nanoparticles constitute a potential health hazard due to their size‐dependent lung deposition and large surface to mass ratio. Exposure to high levels contributes to the risk of developing respiratory and cardiovascular diseases, as well as of lung cancer. Particle‐induced acute phase response may be an important mechanism of action of particle‐induced cardiovascular disease. Here, the authors review new important scientific evidence showing causal relationships between inhalation of particle and nanomaterials, induction of acute phase response, and risk of cardiovascular disease. Particle‐induced acute phase response provides a means for risk assessment of particle‐induced cardiovascular disease and underscores cardiovascular disease as an occupational disease. 相似文献
106.
Krajewski Marcin Tokarczyk Mateusz Lewińska Sabina Bochenek Kamil Ślawska-Waniewska Anna 《Metallurgical and Materials Transactions A》2021,52(8):3530-3540
Metallurgical and Materials Transactions A - This work presents the evolution of morphological, structural and magnetic properties of amorphous Fe-Ni wire-like nanochains caused by thermal... 相似文献
107.
Alessandra Colombini Marco Brayda-Bruno Lucia Ferino Giovanni Lombardi Vincenzo Maione Giuseppe Banfi Sabina Cauci 《International journal of molecular sciences》2015,16(2):3722-3739
Recently, the FokI polymorphism (rs2228570) in the vitamin D receptor gene (VDR) and conventional risk factors were associated with spine disorders in the Italian population, but without gender analysis. Two-hundred and sixty-seven patients (149 males, 118 females) with lumbar spine disorders were assessed by magnetic resonance imaging (MRI) and 254 (127 males, 127 females) asymptomatic controls were enrolled. The exposure to putative risk factors was evaluated and FokI polymorphism was detected by PCR-restriction fragment length polymorphism (PCR-RFLP). An association between lumbar spine pathologies and higher than average age; overweight; family history; lower leisure physical activity; smoking habit; higher number of hours/day exposure to vibration and more sedentary or intense physical job demand was observed in male patients. In contrast, in females, only higher age, overweight, family history and lower leisure physical activity were risk factors. FF genotype was a 2-fold risk factor to develop discopathies and/or osteochondrosis concomitant with disc herniation for both gender patients, while heterozygous Ff was protective for females only. In males only ff genotype was protective for discopathies and/or osteochondrosis and F allele was a 2-fold risk factor for hernia; discopathies; discopathies and/or osteochondrosis. Sex-related differences in voluntary behaviors, exposure to environmental risks and genetic background could be crucial for a gender-differentiated management of patients with spine disorders. 相似文献
108.
Austenitic and ferritic duplex stainless steels, DSS, have recently suffered from hydrogen stress induced cracking, HISC, in subsea components with a cathodic protection. This paper provides discussions on possible HISC mechanisms. HISC initiation can occur at the ferritic grain boundaries and phase boundaries at a stress lower than the yield strength, but dominantly at phase boundaries at a stress higher than the yield strength. EBSD analysis shows that HISC in DSS results from the interaction between the dynamic plasticity by creep and hydrogen diffusion. A model on the formation of microstresses in these two phases under creep conditions is proposed, which explains why HISC occurs mainly in the ferritic phase. Discontinuous two‐dimensional HISC paths were observed. The austenitic phase acts as obstacles for crack propagation. The fracture covers “valleys” and “peaks” with the cleavage ferrite and the austenite with microfacets or striations due to the hydrogen‐enhanced localized‐plasticity. 相似文献
109.
A comparison of Euclidean Distance,Travel Times,and Network Distances in Location Choice Mixture Models 总被引:1,自引:0,他引:1
Buczkowska Sabina Coulombel Nicolas de Lapparent Matthieu 《Networks and Spatial Economics》2019,19(4):1215-1248
Networks and Spatial Economics - This article investigates the selection of a distance measure in location modeling. While in the empirical literature the choice usually boils down to picking one... 相似文献
110.