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91.
The effects of Neodymium (Nd) on the electrical properties of low density polyethylene in relation with morphological aspects are reported in this article. Scanning electron microscopy and optical microscopy revealed a quasi-uniform dispersion of Nd particles in polyethylene, both individual particles and clusters being observed. Contact angle measurements showed a decrease of contact angle values and, thus, of surface hydrophobicity, with the increase of Nd content. The addition of Nd in polyethylene determined the increase of electric permittivity and conductivity. The variation of permittivity was explained considering the influence of polar species (additives, oxidation products, neodymium oxide), highlighted by Fourier transform infrared analysis. 相似文献
92.
Dana L. Morgan Gerry Triani Mark G. Blackford N. A. Raftery Ray L. Frost Eric R. Waclawik 《Journal of Materials Science》2011,46(2):548-557
In this study, the mechanism of precursor dissolution and the influence of kinetics of dissolution on titanate nanotube formation
were investigated. This comparative study explored the dissolution kinetics for the case of commercial titania powders, one
composed of predominantly anatase (>95%) and the other rutile phase (>93%). These nanoparticle precursors were hydrothermally
reacted in 9 mol L−1 NaOH at 160 °C over a range of reaction times of between 2 and 32 h. The high surface area nanotube-form product was confirmed
using X-ray diffraction, FT-Raman spectroscopy, and transmission electron microscopy. The concentration of nanotubes produced
from the different precursors was established using Rietveld analysis with internal and external corundum standardization
to calibrate the absolute concentrations of the samples. Interpretation of the dissolution process of the precursor materials
indicated that the dissolution of anatase proceeds via a zero-order kinetic process, whereas rutile dissolution is through
a second-order process. The TiO2 nanostructure formation process and mechanism of TiO2 precursor dissolution was confirmed by non-invasive dynamic light scattering measurements. Significant observations are that
nanotube formation occurred over a broad range of hydrothermal treatment conditions and was strongly influenced by the order
of precursor dissolution. 相似文献
93.
94.
King Eden B.; Dunleavy Dana G.; Dunleavy Eric M.; Jaffer Salman; Morgan Whitney Botsford; Elder Katie; Graebner Raluca 《Canadian Metallurgical Quarterly》2011,17(1):54
Although scholars agree that traditional forms of discrimination have generally been supplanted by subtler interpersonal manifestations of discrimination, it is yet unknown whether targets of these behaviors or the American judicial branch recognize such negative behaviors as violations of extant law. Extending research and theory, we propose that denigrating messages toward women and ethnic minorities (i.e., microaggressions) emerge in workplace interactions and are sometimes interpreted as discrimination. Specifically, this research explores the presence, severity, and frequency of microaggressions that appear in a random sample of race and gender discrimination cases in federal court dockets since the year 2000. The results suggest that microinsults, microinvalidations, and microassaults are reported in a variety of discrimination claims. However, only overt and intentional forms of microaggressions (microassaults) increased the likelihood that decisions favored plaintiffs. Thus, there may be a disconnect between forms of discrimination perceived by claimants and how those forms are evaluated by the legal system that protects victims of discrimination. This potential misalignment of science and practice is discussed, as are directions for future research. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
95.
Voss Horrell Sarah C.; Holohan Dana R.; Didion Lea M.; Vance G. Todd 《Canadian Metallurgical Quarterly》2011,42(3):283
Reports an error in "Treating traumatized OEF/OIF veterans: How does trauma treatment affect the clinician" by Sarah C. Voss Horrell, Dana R. Holohan, Lea M. Didion and G. Todd Vance (Professional Psychology: Research and Practice, 2011[Feb], Vol 42[1], 79-86). The word “While” was erroneously inserted in the first sentence of the “Clinician Factors” section. The corrected sentence is provided in the erratum. (The following abstract of the original article appeared in record 2011-04544-011.) The authors of this article describe the rewards and challenges for clinicians treating veterans who have served in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). Issues of vicarious trauma, secondary traumatic stress, compassion fatigue, and burnout are defined and reviewed, as are compassion satisfaction and posttraumatic growth. Patient, clinician, and organizational characteristics that are likely to affect clinicians working with this clinical population are discussed. Patient factors that may increase strain on clinicians are discussed such as age, likelihood of redeployment, comorbid conditions, attendance issues, and elevated risk for suicide and aggression. Clinician factors, such as theoretical orientation, training, supervision, military affiliation, personal trauma history, spirituality, social support, and self-care, are also discussed as possible risk and protective factors for vicarious trauma and burnout. Organizational influences, such as caseload size and diversity, clinician control and autonomy, use of evidence-based practices, availability of resources, rural isolation, and the philosophy of the clinic, are further discussed. Recommendations for ameliorating risks are discussed relative to each area and include allowing clinicians to plan their own appointments so as to balance their caseload of OEF/OIF veterans, attending to self-care practices, and having a supportive team with thorough training in evidence-based practices. Future empirical research is needed on risk and resiliency factors for clinicians working with traumatized OEF/OIF veterans given that this population is likely to grow. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
96.
97.
98.
Jian-Gong Cheng Reinhard Gabl Dana Pitzer Robert Primig Matthias Schreiter Wolfram Wersing 《Journal of the American Ceramic Society》2003,86(10):1786-1788
Columnar and (100)-oriented LaNiO3 thin films were prepared on silicon substrates by a chemical solution deposition (CSD) process using a 0.05 M solution. By reducing the individual layer thickness to 10 nm, columnar LaNiO3 films with a lateral grain size of ∼120 nm were obtained. The success of this approach required restricting the individual layer thickness to a value below the grain size observed for equiaxed films. This change in microstructure resulted in an improvement in conductivity. The columnar LaNiO3 film with a thickness of 300 nm showed a resistivity of 4.5 × 10−5 Ω·cm, which is lower by one order of magnitude than that of fine-grain equiaxed films that typically result from CSD methods. 相似文献
99.
100.
Lent Robert W.; Hoffman Mary Ann; Hill Clara E.; Treistman Dana; Mount Mandy; Singley Daniel 《Canadian Metallurgical Quarterly》2006,53(4):453
Two versions of a counselor self-efficacy (CSE) measure were administered to 110 prepracticum counselors: a general version, assessing perceived capability to perform basic helping skills and manage the session process with clients generally; and a client-specific version, tapping capability to perform the same behaviors with a specific, current client. Client-specific CSE was found to (a) relate moderately to strongly with general CSE over the course of four counseling sessions, (b) increase significantly over sessions, and (c) account for unique variance in counselors' evaluations of the quality of their sessions. Although it was not a useful direct predictor of clients' session ratings, higher client-specific CSE was associated with greater congruence between counselors' and clients' perceptions of session quality. Implications for further research and training are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献