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41.
Solvent usage is often an integral part of manufacturing process, whether it is chemical or another industrial sector. Thus, this unavoidable choice of a specific solvent for a desired manufacturing process can have profound economical, environmental, and societal implications. Some of the impacts are long lasting especially from an environmental perspective, which has been well documented in the scientific literature. The pressing need to develop alternative solvents for manufacturing processes originates, in part, from these implications and constitutes an essential strategy under an emerging field of green chemistry. Whereas there have been excellent advances in developing several alternative clean solvents, it is unlikely that the one solvent will be a panacea for various chemical protocols. This article provides some examples of using water as an alternative solvent for chemical reactions with wide-ranging possibilities that include direct use of water soluble renewable materials, C–C bond forming reactions using organometallic reagents, and exploiting the use of alternate energy sources such as solar, microwave and ultrasound in accelerating chemical syntheses.An erratum to this article can be found at  相似文献   
42.
There is accumulating evidence that driver distraction and driver inattention are leading causes of vehicle crashes and incidents. However, as applied psychological constructs, they have been inconsistently defined and the relationship between them remains unclear. In this paper, driver distraction and driver inattention are defined and a taxonomy is presented in which driver distraction is distinguished from other forms of driver inattention. The taxonomy and the definitions provided are intended (a) to provide a common framework for coding different forms of driver inattention as contributing factors in crashes and incidents, so that comparable estimates of their role as contributing factors can be made across different studies, and (b) to make it possible to more accurately interpret and compare, across studies, the research findings for a given form of driver inattention.  相似文献   
43.
During purification process development and analytical characterization, a recombinant human monoclonal antibody, referred to as rmAb1, showed an anomalous charge heterogeneity profile by cation-exchange chromatography (CIEC), characterized by extremely high retention and poor resolution between charge variants. Mass spectrometry-based footprinting methodologies that include selective labeling of lysine with sulfosuccinimidyl acetate and arginie with p-hydroxyphenylglyoxal were developed to map the positive charges on the rmAb1 surface. On the basis of the average percentages of labeling obtained for the lysine and arginine residues by peptide mapping analysis, the positive charges were more distributed on the surface in the Fab region than in the Fc region of rmAb1. By a comparative study of in-solution and on-resin labeling reaction dynamics, seven positively charged residues were identified to bind to the cation-exchange resin and they were located in the variable domains. Among them, three lysine and one arginine residues appeared to cluster together on the surface to form a positive charge patch. When the charge patch residues were neutralized by chemical labeling, rmAb1 exhibited a more typical CIEC retention time, confirming that the charge patch was responsible for the atypical CIEC profile of rmAb1. To our knowledge, this work is the first report revealing the amino acid composition of a surface charge patch on therapeutic monoclonal antibodies.  相似文献   
44.
A novel fluorescent zinc sensor was designed and synthesized on ordered mesoporous silica material, MCM-41, with N-(quinolin-8-yl)-2-[3-(triethoxysilyl)propylamino]acetamide (QTEPA; 3) using a simple one-step molecular self-assembly of the silane. The solution and solid samples were characterized using solid-state nuclear magnetic resonance, transmission electron microscopy, diffuse-reflectance infrared Fourier transform, and thermogravimetric analysis techniques. The QTEPA-modified MCM-41 (4) shows 3-fold fluorescence emission enhancement and about a 55 nm red shift upon addition of 1 μM Zn(II) ions in a Tris-HCl (pH 7.22) aqueous buffer solution. The UV-vis absorption maximum is at 330 ± 5 nm, and the fluorescence emission maximum wavelength is at 468 nm, with an increase in quantum yield from 0.032 to 0.106 under the same conditions. The presence of other metal ions has no observable effect on the sensitivity and selectivity of 4. This system selectively detects Zn(II) ions with submicromolar detection to a limit of 0.1 μM. The MCM-41-based systems have the advantage that they can be employed in aqueous solutions without any aggregation.  相似文献   
45.
The experiments examined the effects of prelimbic-infralimbic inactivation in rats on the acquisition and reversal learning of different discrimination tasks: 2- or 4-choice odor discrimination in Experiments 1 and 2, the shift from 2-choice odor discrimination to 2-choice place discrimination in Experiment 3, and the shift from 2-choice place to 2-choice odor discrimination in Experiment 4. Infusions of 2% bupivacaine did not impair performance in the odor discrimination tests. Prelimbic-infralimbic inactivation did not impair acquisition but did impair the shift from an odor to a place discrimination and vice versa. Analysis of the errors revealed that the deficit was due to perseveration of the previously learned strategy. The selective deficits observed in the odor-place tests suggest that the prelimbic-infralimbic areas enable behavioral flexibility when conditions demand inhibiting the use of one type of attribute information and learning a new type of attribute information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
Principal component analysis was applied to XRD data from a series of Mg(OH)2 samples prepared under different hydrothermal conditions from bischofite (MgCl2.6H2O) and carnallite (KCl.MgCl2.6H2O), owing to differences in full width at half-maximum (fwhm) as well as in the intensity ratio I001/I101 of the respective diffraction peaks. According to the PCA results, the four principal components are able to explain 93% of the total variance and the samples can be classified into four main groups. For instance, the principal component PC1 can be interpreted as the crystallite size along the 101 direction since it is related to the fwhm of this peak. On the other hand, PC3 is related to orientation effects along 001 and 101 directions as it is dominated by the relative intensities of the two peaks. Finally, a comparison of the scanning electron microscopy images of the samples classified in each group revealed that in most of the cases a distinct morphology predominates within each group, which can be explained on the basis of the brucite growth mechanism.  相似文献   
47.
Abstract

An alternative method for the determination of mercury (Hg) in solid samples is presented in this article. Gaseous Hg is evolved when a solid sample is heated above 500°C in the presence of oxygen. The evolved Hg is collected on silver wool and is analyzed using cold vapor methods. We have found greater than 95% Hg recovery with various sediment and ash standards.  相似文献   
48.
The globalization of the world's food trade calls for rapid and accurate detection of foodborne pathogens to ensure safety of foods for human consumption, to prevent outbreaks and management of foodborne infectious diseases. Currently, commercial detection methods for pathogenic microbials require multiple days for sample‐to‐answer results. In this study, we demonstrated a highly sensitive and rapid detection of a microbial pathogen using Molecular Mirroring (M2) technology and Lab‐in‐the‐Box system based on nuclear magnetic resonance that works rapidly and efficiently for the detection of Salmonella. This technology detected Salmonella at 1 cfu/reaction in water. In tuna, the M2 technology detected 1 cfu/g with 5 hr of enrichment and analysis with a T2 signal of 342 ms. In addition to sensitive detection and minimal enrichment, this methodology detected pathogens from inhibitory mediums. Therefore, this technology can be widely applied to other fields such as environmental monitoring, public health and safety, national security, and medical diagnosis.

Practical applications

The combination of molecular biology and nuclear magnetic resonance technology represents a novel, rapid, sensitive, and highly specific methodology for the detection of Salmonella spp. in tuna compared to standard conventional methods. Practical applications of the M2 technology have been tested with human samples, animal samples, and food samples to detect microbial pathogens before and after food processing, thus is ideal to protect public health and to ensure food safety. Furthermore, this biosensor analytical technology can be applied to almost any medium or target of interest in the field of food safety, clinical diagnostics, and biosurveillance.  相似文献   
49.
Examined the ability of neuropsychological measures to assess independent functioning with 154 geriatric medical patients. Ss completed the Mattis Dementia Rating Scale, Boston Naming Test, Wechsler Memory Scale (WMS), and Functional Independence Measures. Both the neuropsychological composite and the severity index of comorbid disease status were predictors of independent functioning. Results underscore the importance of collecting information on disease status as well as performing neuropsychological screening on geriatric patients during inpatient rehabilitation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
In this study we assessed the incidence of and the risk factors for date rape and other forms of male-against-female sexual aggression (SA) in dating situations. Over the course of two semesters, 341 women and 294 men anonymously completed questionnaires. They were asked to describe their most recent date (to provide normative data on dating) and their worst experience with SA during a date, if applicable. We assessed possible risk factors in three ways: (a) For people who had been involved in SA, we compared the characteristics of their SA dates and their recent dates; anything occurring more often on SA dates than on recent dates might be a risk factor. (b) We compared the most recent dates of people who had versus had not experienced SA to identify differences in their date habits. (c) We compared attitudes of people who had versus had not been involved in SA. Results showed that 77.6% of the women and 57.3% of the men had been involved in some form of SA; 14.7% of the women and 7.1% of the men had been involved in unwanted sexual intercourse. Variables that appear to be risk factors are the man's initiating the date, paying all the expenses, and driving; miscommunication about sex; heavy alcohol or drug use; "parking"; and men's acceptance of traditional sex roles, interpersonal violence, adversarial attitudes about relationships, and rape myths. The length of time that dating partners have known each other seems unrelated to the risk of SA. Implications for rape-prevention programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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