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排序方式: 共有366条查询结果,搜索用时 15 毫秒
81.
This research tested the relation of socioeconomic status (SES), indexed by parental education, to stress-coping variables and substance use in a sample of 1,391 adolescents. Lower education was related to higher level of adolescent substance use, lower levels of protective factors, and higher levels of risk factors. Mediation analyses indicated that the effect of education on adolescent substance use was mediated through relationships to parental support, academic competence, behavioral competence, negative life events, and friends' substance use. Moderation analyses indicated that adolescents from lower education families were more vulnerable to risk factors but also derived more benefit from protective factors. Multiple-group analysis indicated that moderation was attributable to larger paths in the lower education group for negative events and friends' use. Implications for the relation between SES and health risk are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Assessing the contact‐activation of coagulation during hemodialysis with three different polysulfone filters: A prospective randomized cross‐over trial 下载免费PDF全文
Igor Salvadè Rosaria Del Giorno Donato Gaetano Luca Gabutti 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(3):375-384
Introduction: During hemodialysis (HD) the interaction of the blood with the dialyzer triggers both an inflammatory reaction and an activation of the coagulation cascade. An accepted parameter to quantify the extent of coagulation activation during HD is not available. This study aims to evaluate its amplitude, comparing dialyzers made of different polysulfone polymers, by measuring D‐dimers in the filter‐rinsing fluids (Frf) and to test whether Frf D‐dimers are suitable candidate markers to assess contact coagulation activation during HD. Methods: In a prospective, cross‐over study 41 hemodialysis patients were randomly allocated to nine HD sessions with three types of polysulfone membranes: Filter A: Poliflux®RevaclearMAX; Filter B: Helixone®Fx80, Filter C: Polyflux®H210. Findings: A total of 117 HD sessions were studied. The mean (SD) filter (Frf) D‐dimers were 0.19 µg/L (0.56) for Filter A; 0.66 µg/L (2.81) for Filter B; 0.33 µg/L (1.13) for Filter C. Significant differences were found: A vs. B (P < 0.01), A vs. C (P = 0.01); B vs. C not significant. A large between‐patient variability of D‐dimer filter levels was found. D‐Dimers in blood showed a similar trend but differences were not significant. Discussion: The contact activation of coagulation during HD may also vary among filters made up with similar polysulfones. D‐dimer in the filter rinsing fluid but not in the blood can be considered a candidate marker for the evaluation of thrombogenicity during HD. Further studies are needed to elucidate the mechanism(s) and to confirm the usefulness of filter rinsing fluid D‐Dimers as a clotting activation marker during HD. 相似文献
83.
The effect of addition of tin on the catalytic activity of Ru/C catalysts has been investigated in the liquid phase hydrogenation of -methylstyrene and hydrocinnamaldehyde. On increasing the Sn content, the amount of CO chemisorbed decreases, indicating a decrease in the number of Ru surface atoms. In the hydrogenation of -methylstyrene the specific activity of Ru (calculated per Ru surface atom) remains constant regardless of the Sn/Ru ratio. An increase of specific activity is however observed in the hydrogenation of hydrocinnamaldehyde. It is suggested that tin, present mainly as Sn ions, enhances the reactivity of the C=O group. 相似文献
84.
Libertini Giacinto; Donato Alberto Di 《Protein engineering, design & selection : PEDS》1992,5(8):821-825
A computer program, which runs on MS-DOS personal computers,is described that assists in the design of synthetic genes codingfor proteins. The goal of the program is the design of a genewhich (0 contains as many unique restriction sites as possibleand (ii) uses a specific codon usage. The gene designed accordingto the criteria above is (i) suitable for modular mutagenesisexperiments and (ii) optimized for expression. The program 'reverse-translates'protein sequences into degenerated DNA sequences, generatesa map of potential restriction sites and locates sequence positionswhere unique restriction sites can be accommodated. The nucleicacid sequence is then refined according to a specificcodon usage to remove any degeneration. Unique restriction sites,if potentially present, can be forced into thedegenerated nucleic acid sequence by using 'priority codes'assigned to different restriction sequences. 相似文献
85.
Giuseppe Aceto Alessio Botta Walter de Donato Antonio Pescapè 《Computer Networks》2013,57(9):2093-2115
Nowadays, Cloud Computing is widely used to deliver services over the Internet for both technical and economical reasons. The number of Cloud-based services has increased rapidly and strongly in the last years, and so is increased the complexity of the infrastructures behind these services. To properly operate and manage such complex infrastructures effective and efficient monitoring is constantly needed.Many works in literature have surveyed Cloud properties, features, underlying technologies (e.g. virtualization), security and privacy. However, to the best of our knowledge, these surveys lack a detailed analysis of monitoring for the Cloud. To fill this gap, in this paper we provide a survey on Cloud monitoring. We start analyzing motivations for Cloud monitoring, providing also definitions and background for the following contributions. Then, we carefully analyze and discuss the properties of a monitoring system for the Cloud, the issues arising from such properties and how such issues have been tackled in literature. We also describe current platforms, both commercial and open source, and services for Cloud monitoring, underlining how they relate with the properties and issues identified before. Finally, we identify open issues, main challenges and future directions in the field of Cloud monitoring.1 相似文献
86.
Giovanni Ambrosi Simona Bartocci Laurent Basara Roberto Battiston William J. Burger Luca Carfora Guido Castellini Piero Cipollone Livio Conti Andrea Contin Cinzia De Donato Cristian De Santis Francesco M. Follega Cristina Guandalini Maria Ionica Roberto Iuppa Giuliano Laurenti Ignazio Lazzizzera Mauro Lolli Christian Manea Laura Marcelli Giuseppe Masciantonio Matteo Mergé Giuseppe Osteria Lorenzo Pacini Francesco Palma Federico Palmonari Beatrice Panico Laura Patrizii Francesco Perfetto Piergiorgio Picozza Michele Pozzato Matteo Puel Irina Rashevskaya Ester Ricci Marco Ricci Sergio Bruno Ricciarini Valentina Scotti Alessando Sotgiu Roberta Sparvoli Bruno Spataro Vincenzo Vitale 《中国科学:技术科学(英文版)》2018,61(5):643-652
CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2~(nd), 2018 from the Jiuquan Satellite Launch Center(China). 相似文献
87.
Giuseppe Papa Antonino Romano Donato Quaratino Marina Di Fonso Marinella Viola Maria Cristina Artesani Sabina Sernia Mario Di Gioacchino Alberto Venuti 《The Science of the total environment》2001,270(1-3)
In the last few years Cupressus sempervirens has been identified as the cause of an increasing number of cases of late winter-early spring pollinosis in Mediterranean countries. We conducted a 4-year retrospective study of a large group of subjects with documented allergic respiratory disease in order to determine the prevalence, clinical significance and annual rate of sensitization to C. sempervirens pollen. Anamnestic data and skin prick tests (SPT) with common aeroallergens and C. sempervirens extract were collected from 1397 subjects (712 male and 685 female) resident in Latium, a region in central Italy, with complaints related to upper- or lower-respiratory-tract disorders or conjunctival disease. Two hundred and forty-three subjects (17.4%) showed positive results to C. sempervirens extract; 47 (19.3%) of them were monosensitized. The annual sensitization rate of SPT positivity to C. sempervirens varied from 7.2% in 1995 to 22% in 1998. All the subjects monosensitized to cypress pollen had symptoms from January through April. Our study suggests that sensitivity to C. sempervirens is responsible for respiratory symptoms in an increasing percentage of subjects. Further studies are needed to determine its frequency at the national level. 相似文献
88.
G. Messina V. Modafferi S. Santangelo P. Tripodi M.G. Donato M. Lanza S. Galvagno C. Milone E. Piperopoulos A. Pistone 《Diamond and Related Materials》2008,17(7-10):1482-1488
The crucial role of precursor gas (PG) and of catalyst support (CS) in the growth of multi-walled C nanotubes (MWCNTs) by iron-catalysed chemical vapour deposition (CVD) is evidenced. This is accomplished by comparing structural and morphological properties of MWCNTs synthesised by the use of different PGs (ethane and isobutane) and CSs (silica and alumina). The results of analyses, carried out on catalysts and C deposits by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS), thermo-gravimetry (TG) and X-ray diffraction (XRD), demonstrate that Al2O3-supported catalysts are more efficient than SiO2-supported ones in decomposing hydrocarbons. The use of i-C4H10 as PG allows reducing Fe-encapsulation and improving yield (YC) and selectivity, so as the large-scale production (YC > 900 wt.%) of high-quality nanotubes can be operated even at moderate reaction temperature (600 °C) after proper calibration of Fe-load (29 wt.%) and catalyst reduction temperature (500 °C). 相似文献
89.
Silvia Cerri Cristina Ghezzi Gerardo Ongari Stefania Croce Micol Avenali Roberta Zangaglia Donato A. Di Monte Enza Maria Valente Fabio Blandini 《International journal of molecular sciences》2021,22(4)
Heterozygous mutations in the GBA gene, encoding the lysosomal enzyme glucocerebrosidase (GCase), are the strongest known genetic risk factor for Parkinson’s disease (PD). The molecular mechanisms underlying the increased PD risk and the variable phenotypes observed in carriers of different GBA mutations are not yet fully elucidated. Extracellular vesicles (EVs) have gained increasing importance in neurodegenerative diseases since they can vehiculate pathological molecules potentially promoting disease propagation. Accumulating evidence showed that perturbations of the endosomal–lysosomal pathway can affect EV release and composition. Here, we investigate the impact of GCase deficiency on EV release and their effect in recipient cells. EVs were purified by ultracentrifugation from the supernatant of fibroblast cell lines derived from PD patients with or without GBA mutations and quantified by nanoparticle tracking analysis. SH-SY5Y cells over-expressing alpha-synuclein (α-syn) were used to assess the ability of patient-derived small EVs to affect α-syn expression. We observed that defective GCase activity promotes the release of EVs, independently of mutation severity. Moreover, small EVs released from PD fibroblasts carrying severe mutations increased the intra-cellular levels of phosphorylated α-syn. In summary, our work shows that the dysregulation of small EV trafficking and alpha-synuclein mishandling may play a role in GBA-associated PD. 相似文献
90.
Paride Papadia Laura Del Coco Innocenzo Muzzalupo Marco Rizzi Enzo Perri Gianluigi Cesari Vito Simeone Donato Mondelli Francesco P. Schena Francesco P. Fanizzi 《Journal of the American Oil Chemists' Society》2011,88(10):1463-1475
Mono-varietal extra virgin olive oils were micro-extracted from drupes that were selectively collected from 28 trees distributed
in five different Southern Italian Apulian areas. Nuclear Magnetic Resonance (NMR) profiles of these oil samples were correlated
to the genetic (young green material) and soil (samples collected within the foliage projection) data of the tree of origin.
Genetic analysis, performed on the samples using SSRs (Simple Sequence Repeats) by 9 microsatellite loci, confirmed the specific
cultivar assignment (among Cima di Mola, Coratina, Ogliarola, and Oliva Rossa cultivars). Chemometric methods applied to 1H-NMR spectroscopic data were used for cultivar and geographical origin discrimination of the studied extra virgin olive oils.
Linear Discriminant Analysis (LDA) afforded a high reliability degree for discriminating cultivars (almost 90% of prediction
ability), and a good assigning ability for the geographical origin (Ogliarola and Coratina samples used as subsets). Soil
analyses were performed for each tree. Regression analysis was applied to soil composition in order to correlate available
nutrients and total metals with the content of fatty acids and minor components present in monovarietal extra virgin olive
oils. In the case of oleic and linoleic fatty acids, and for some terpenes, B, Cr, Mn, Zn were found to give significant correlations.
Zn and Mn were the most significant trace elements for all the correlations found (p < 0.01). The results obtained (genetic, spectroscopic and soil analyses) are discussed as a multidisciplinary approach for
setting up a strategy for a cultivar and/or geographic origin certification committed database construction. 相似文献