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排序方式: 共有114条查询结果,搜索用时 15 毫秒
101.
Greta Minelgaite Asbjørn Haaning Nielsen Morten Lauge Pedersen Jes Vollertsen 《Urban Water Journal》2017,14(1):53-60
Photodegradation of carbendazim, diuron and terbutryn was investigated at controlled laboratory conditions under UV light and under natural sunlight. Demineralized water and two different waters from stormwater retention ponds were used. An observed decline in biocide concentration was related to the accumulated light energy during the degradation time. Diuron and terbutryn were degradable under UV light following 1st order degradation kinetics, while no significant decrease of carbendazim was observed throughout the duration of experiments. Photodegradation of diuron and terbutryn was slightly faster in demineralized water compared with pond water. The outdoors experiments showed limited degradation of the compounds for the duration of the test (8–17 days). The results emphasize the importance of water type, the wavelength and energy of the light when investigating pollutant’s photo fate. Also, this study indicates that photodegradation is not a major process contributing to the removal of carbendazim, diuron and terbutryn in stormwater retention ponds. 相似文献
102.
José Garcia Greta LindwallOrlando Prat Karin Frisk 《International Journal of Refractory Metals and Hard Materials》2011,29(2):256-259
Kinetics of formation of fcc-free layers on Co-W-Ti-Ta-Nb-C-N cemented carbides was investigated by experimental methods and DICTRA simulations. The layer formation obeys a parabolic law, indicating a diffusion-controlled process. For DICTRA simulations, the influence of the mobilities for all diffusing elements in the liquid binder phase at the sintering temperature was investigated. The best agreement between experimental and simulations was obtained considering that the mobility of all metallic elements is two times slower compared with the mobility of the non-metallic elements. 相似文献
103.
In order to alleviate the current food security situation the world is faced with, it is essential to investigate meat sources which have the potential to be used in a sustainable manner. This review provides substantial arguments to prove the viability of sport hunted wildfowl as a food source in Southern Africa. However, before the use of wildfowl meat can be realised, there are certain challenges to overcome in order to ensure meat of the best possible quality reaches the consumer. Important aspects to consider regarding the eating quality of wildfowl meat are identified and include the physical activity of the different portions and muscle fibre types, diet, breeding, age and gender as well as the post mortem handling/ageing of the meat. The safety issues involved in producing gamebird meat i.e. shot contamination (microbial or lead), are also discussed. Other areas that warrant scientific research include investigating the intrinsic and extrinsic factors that may have an influence on the ultimate meat quality and exploring possible techniques of improving the eating quality of wildfowl meat. The insights these investigations will provide have the potential to increase the commercial viability, directly or indirectly, of African wildfowl meat and thus contribute to food security. 相似文献
104.
Accelerating math development in Head Start classrooms. 总被引:1,自引:0,他引:1
Arnold David H.; Fisher Paige H.; Doctoroff Greta L.; Dobbs Jennifer 《Canadian Metallurgical Quarterly》2002,94(4):762
Teachers implemented a 6-week classroom intervention designed to promote emergent math skills and math interest in preschool-aged children. Teachers in experimental classrooms incorporated math-relevant activities into their daily routine during circle time, transitions, mealtime, and small-group activities. Control classrooms engaged in their typical activities. After the program, experimental children scored significantly higher than control children on a standardized test of math ability and enjoyed math activities more than the control children, as measured by both teacher and self-report. Teachers rated the program as highly satisfactory and reported that they increased their own enjoyment and skill in implementing math activities in their classrooms. The intervention effects were largely accounted for by substantial gains by boys, whereas girls showed much smaller program response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Lili Arabuli Igor A. Iashchishyn Nina V. Romanova Greta Musteikyte Vytautas Smirnovas Himanshu Chaudhary
eljko M. Svedrui Ludmilla A. Morozova-Roche 《International journal of molecular sciences》2021,22(16)
The amyloid cascade is central for the neurodegeneration disease pathology, including Alzheimer’s and Parkinson’s, and remains the focus of much current research. S100A9 protein drives the amyloid-neuroinflammatory cascade in these diseases. DOPA and cyclen-based compounds were used as amyloid modifiers and inhibitors previously, and DOPA is also used as a precursor of dopamine in Parkinson’s treatment. Here, by using fluorescence titration experiments we showed that five selected ligands: DOPA-D-H-DOPA, DOPA-H-H-DOPA, DOPA-D-H, DOPA-cyclen, and H-E-cyclen, bind to S100A9 with apparent Kd in the sub-micromolar range. Ligand docking and molecular dynamic simulation showed that all compounds bind to S100A9 in more than one binding site and with different ligand mobility and H-bonds involved in each site, which all together is consistent with the apparent binding determined in fluorescence experiments. By using amyloid kinetic analysis, monitored by thioflavin-T fluorescence, and AFM imaging, we found that S100A9 co-aggregation with these compounds does not hinder amyloid formation but leads to morphological changes in the amyloid fibrils, manifested in fibril thickening. Thicker fibrils were not observed upon fibrillation of S100A9 alone and may influence the amyloid tissue propagation and modulate S100A9 amyloid assembly as part of the amyloid-neuroinflammatory cascade in neurodegenerative diseases. 相似文献
106.
Jacobson Joseph L.; Jacobson Sandra W.; Schwartz Pamela M.; Fein Greta G.; Dowler Jeffrey K. 《Canadian Metallurgical Quarterly》1984,20(4):523
The multiple effects model of teratological exposure predicts that neonatal deficits associated with intrauterine exposure to small doses of a potentially teratogenic agent will vary considerably across individuals. This hypothesis was tested in a sample of 242 newborns exposed prenatally to low levels of polychlorinated biphenyls (PCBs) from maternal consumption of contaminated lake fish and 71 control infants whose mothers did not eat these fish. Behavioral outcomes were assessed using the Brazelton Neonatal Behavioral Assessment Scale (NABS). Contaminated fish consumption predicted motoric immaturity, poorer lability of states, a greater amount of startle, and more abnormally weak (hypoactive) reflexes. The most highly exposed Ss were more likely than controls to be classified as "worrisome" on 3 NBAS clusters. Results from a stepwise regression analysis are consistent with the multiple effects model, indicating that some affected Ss were born small and/or early, whereas others exhibited one or another of the behavioral deficits. The analysis indicated that 12.2% of the variance in contaminated fish consumption was associated with measurable neonatal deficits. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
A full option method for determining impact takes into account citations to all cited publications, instead of limiting the
analysis to ISI-publications only, as usually done in the standard method. The method was tested for the 258 early Ghent professors,
teaching in 6 different faculties. The impact of monographs is, in general, much larger than the impact of articles (whether
of ISI-type or not). This result remains valid for all six faculties separately. Limiting the bibliometric visibility to ISI-publications
reduces the number of citations to only 16%. Bibliometric spectra are presented, in which citations, cited publications and
their impact are shown in function of the year of publication. The number of cited publications is always important to expose
the influence of activity (production) upon bibliometric scores. For the faculty of Arts, the citations to early professors
are compared with those obtained for the presentday generation: the bibliometric spectrum for the former group is rather discontinuous
(showing a large erosion in the number of citations by year), whereas that of the latter is continuous. The Ghent citation
data are also compared with those given internationally in the same period. 相似文献
108.
In the current revival of interest in the emotional and mental lives of animals, many investigators have focused attention on mammalian infants that emit distress vocalizations when separated from the home environment. Perhaps the most intensively studied distress vocalization is the ultrasonic vocalization of infant rats. Since its discovery, this vocalization has been interpreted both as a communicatory signal for the elicitation of maternal retrieval and as the manifestation of emotional distress. In contrast, the authors examined the cardiovascular causes and consequences' of the vocalization, and on the basis of this work, they hypothesized that the vocalization is the acoustic by-product of the abdominal compression reaction (ACR), a maneuver that results in increased venous return to the heart. Therefore, the vocalization may be analogous to a sneeze, serving a physiological function while incidentally producing sound. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
The characterization of peptide arrays on gold surfaces designed for the study of peptide-antibody interactions using surface plasmon resonance (SPR) imaging is described. A two-step process was used to prepare the peptide arrays: (i) a set of parallel microchannels was used to deliver chemical reagents to covalently attach peptide probes to the surface by a thiol-disulfide exchange reaction; (ii) a second microchannel with a wraparound design was used as a small-volume flow cell (5 microL) to introduce antibody solutions to the peptide surface. As a demonstration, the interactions of the FLAG epitope tag and monoclonal anti-FLAG M2 were monitored by SPR imaging using a peptide array. This peptide-antibody pair was studied because of its importance as a means to purify fusion proteins. The surface coverage of the FLAG peptide was precisely controlled by creating the peptide arrays on mixed monolayers of alkanethiols containing an amine-terminated surface and an inert alkanethiol. The mole fraction of peptide epitopes was also controlled by reacting solutions containing FLAG peptide and the non-interacting peptide HA or cysteine. By studying variants based on the FLAG binding motif, it was possible to distinguish peptides differing by a single amino acid substitution using SPR imaging. In addition, quantitative analysis of the signal was accomplished using the peptide array to simultaneously determine the binding constants of the antibody-peptide interactions for four peptides. The binding constant, K(ads), for the FLAG peptide was measured and found to be 1.5 x 10(8) M(-1) while variants made by the substitution of alanine for residues based on the binding motif had binding constants of 2.8 x 10(7), 5.0 x 10(6), and 2.0 x 10(6) M(-1). 相似文献
110.
Greta Yorsh Alexander Rabinovich Mooly Sagiv Antoine Meyer Ahmed Bouajjani 《The Journal of Logic and Algebraic Programming》2007,73(1-2):111
We define a new decidable logic for expressing and checking invariants of programs that manipulate dynamically-allocated objects via pointers and destructive pointer updates. The main feature of this logic is the ability to limit the neighborhood of a node that is reachable via a regular expression from a designated node. The logic is closed under boolean operations (entailment, negation) and has a finite model property. The key technical result is the proof of decidability.We show how to express preconditions, postconditions, and loop invariants for some interesting programs. It is also possible to express properties such as disjointness of data-structures, and low-level heap mutations. Moreover, our logic can express properties of arbitrary data-structures and of an arbitrary number of pointer fields. The latter provides a way to naturally specify postconditions that relate the fields on the entry of a procedure to the field on the exit of a procedure. Therefore, it is possible to use the logic to automatically prove partial correctness of programs performing low-level heap mutations. 相似文献