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81.
Pollen used to track structural and functional evolution in plants as well as to investigate the problems relative to plant classification. Pollen characters including ornamentation, shape, apertural pattern, pollen symmetry, colpus length, width, and margins used to detect the similarities and dissimilarities between genera and also species of the same genus. In this study pollen features of 20 monocot species belonging to 15 genera of the Amaryllidaceae, Asparagaceae, Iridaceae, Ixioliriaceae, Liliaceae, and Xanthorrhoeaceae were studied using scanning electron microscopy (SEM) and light microscopy (LM). In this study two species that is Zephyranthes citrina and Tulbaghia violacea were reported for the first time from Pakistan. Pollen grains were visualized with LM. Non‐acetolyzed and acetolyzed pollen were examined using SEM. A taxonomic key was developed to highlight the variation in pollen features in order to make their systematic application for correct species identification.  相似文献   
82.
The Hypnaceae is one of the largest and diversified family among the pleurocarpous mosses which consists of nearly 60 genera and 1,000 species around the world. In Pakistan, it is represented by 15 species and 8 genera. The current research article provides the detail morphological investigation of four different species (genera) of the family Hypnaceae that is, Gollania clarescens, Hypnum revolutum, Homomallium andoi, and Taxiphyllum taxirameum in the Western Himalayas, Pakistan. The research article reports the first SEM study of the leaf surfaces of the studied taxa, along with comprehensive morphological characters of the four species. The main objective of the research project is to present the comparative light and scanning electron microscopic study to discuss the morphology in detail because previously the family is just reported in different bryophyte checklists of the Western Himalayas. Based on results, morphological characters, micromorphological observations, qualitative and quantitative attributes, taxonomic keys for the studied taxa, distribution, and habitat are described. Stereoscope was used to analyze different qualitative characters, and light microscope was used to observe and measure the laminal and alar cells of the leaf. The SEM study reveals many important surface features like cell shape and cell wall. The laminal cells were mostly linear and elongated with thin cell walls. The specimens used for the SEM were air dried, so the laminal cells were somewhat constricted and concaved. The current study project will help to make the contribution in the taxonomy and morphology of this family.  相似文献   
83.
In this study, foliar anatomy and pollen morphology of 10 species of Acanthaceae has been investigated using light and scanning electron microscopy. The study was aimed to highlight the role of microscopy in microteaching at community for proper characterization of plants using palyno‐anatomical characters including pollen type, exine sculpturing, shape of epidermal cells, pattern of anticlinal wall, type and size of stomata, and trichome. Most of the species have polygonal cell shapes but some species have irregular, tetragonal, and pentagonal shape of epidermal cells. The largest epidermal cell length on adaxial and abaxial surface were observed in Asystasia gangetica 66.95 and 87.40 μm whereas least was observed on adaxial surface in Justicia adhatoda 36.9 μm and on abaxial surface in Barleria cristata 35.65 μm. In anatomy, species have diacytic type of stomata, whereas stomata of paracytic type observed in two species, while in A. gangetica cyclocytic type of stomata are present. Quantitively on abaxial surface, largest stomata length 29.9 μm and width 24.30 μm was noted in B. cristata. While shortest stomata length was observed in Ruellia prostrata 25.95 μm whereas minimum width of stomata was examined in Barleria acanthoides 2.05 μm. The diversity of trichomes are present in all species except in Ruellia brittoniana. Acanthaceae can be characterized by exhibiting different pollen morphology having five types of pollen shapes, prolate, spheroidal, perprolate, subprolate, and oblate spheroidal. Exine peculiarities showing variations such as reticulate, granulate, coarsely reticulate, lophoreticulate, perforate tectate, and granulate surface were examined.  相似文献   
84.
Thermophysical analysis of the crustal rocks is important for heat transfer determination and insulation purposes to save energy in buildings.In the presented w...  相似文献   
85.
Investigation of alternative energy sources is need of current time due to growing power crisis and associated environmental issues. Biodiesel is considered as sustainable power source and promising alternative to fossil fuels. Therefore, our current investigation aimed to identify micromorphological characters of 10 novel nonedible oil-yielding seeds through scanning electron microscopy. It was revealed from light microscopic study that there is variation in seed size from 3 to 15 mm in length and 2 to 11 mm in width. Likewise, a huge variation in color was observed such as light green, greenish yellow, blackish brown, and various shades of brown. Presence and absence of Hilum was observed, and compression of seeds varied from depressed, lateral, and dorsoventral. Seed's shape differs from ovate, clavate, triangular ovate, cuneiform, ovoid, and elliptical shape. Seed oil content fall in range of 18–58% (wt/wt). Free fatty acid content of the seeds varies from 0.3 to 3.1 mg KOH/g. Ultrastructure of seeds exhibited huge variation in shape, size, periclinal wall, anticlinal wall, and surface ornamentation. Nonedible seeds varied in wall structure from angular, wavy, dentate entire, irregular, puzzled, elongated, even, and polygonal. The periclinal wall arrangements show alteration from flat, looped, raised, depressed, lofty, even, pentagonal, polygonal, and undulate seed margins. Outcomes of this investigation recommended that scanning electron microscopy could act as a helpful tool in disclosing the hidden micromorphological characters among nonedible oil-yielding seeds and subsequently helping in correct, authentic seed identification and classification as potential feedstock for biodiesel.  相似文献   
86.
87.
Exploration of substitute energy feed‐stocks is the much‐debated topic in the scientific society due to increasing power crises and related ecological concerns. As a source of sustainable energy, biodiesel turns out to be the best alternative to petro fuels. In this context, nonedible oil‐producing seeds might be a potential source for biodiesel production owing to their environment‐friendly nature and cost‐effectiveness. The current study, consequently, deals with the investigation and identification of micro‐morphological characters between six novel nonedible oil‐bearing seeds employing scanning electron microscopy as possible biodiesel feed‐stocks. Light microscopic examinations show that seed size varies from 0.3 to 1.3 cm in width and 0.5 to 1.5 cm in. Additionally, a large difference in seed color ranges from dark brown, black, and various shades of light brown was also witnessed. The FFA content of the seeds ranges in 0.3–4.1 mg KOH/g, and the seed oil content fall in 30–65% (w/w) range. SEM‐mediated seed ultrastructure investigations displays greater variation in seed size, shape, color, periclinal wall shape, and sculpturing and so on. All the seeds differ from rounded, ovoid, ovate, oblong, flattened, and elliptical shape. Greater variation in seed wall structure has been seen from angular, entire, irregular, straight, elongated, smooth, and polygonal. The periclinal wall arrangements show alteration from flat, depressed, elevated, smooth, pentagonal, bullate, and coarse seed margins. The results obtained from the current study suggest that scanning electron microscopy could be a beneficial tool in vitalizing the hidden micromorphological characters among various nonedible oil producing seeds, which eventually helps in exploration, correct identification, seed classification, and authentication in future.  相似文献   
88.
Business process models are used heavily in practice as a basis for process improvement, systems development, and understanding business operations. While prior research has identified a clear need for integrating business rules into graphical business process models, there is little guidance on the circumstances under which business rules should be integrated into business process models. Unnecessary integration may hamper business rule reuse, increase business process model complexity, and lead to difficulties with business rule modification, to name a few. Accordingly, it is important to understand when such integration is appropriate. The aim of this article is to address this need for guidance on when business rules should be integrated in process models, and when they should remain separate. To this end, we explain 12 factors posited to influence such modeling decisions, conduct an empirical study to identify their importance, and develop empirically based modeling guidelines that inform business rule modeling decisions.  相似文献   
89.
A simple and affordable high-performance thin-layer chromatographic (HPTLC) method has been established for simultaneous analysis of colchicine (CL) and gallic acid (GA), which are present together in a complex commercial polyherbal drug (Habb-e-Irqun-Nisa) in tablet dosage forms. The chromatographic separation was carried out on pre-coated silica gel 60 GF254 plates with ethyl acetate/acetonitrile/water/formic acid/N-dimethylformamide 7.5:1:0.5:0.5:0.5 (v/v) as mobile phase. The plates were developed to a distance of 9.0 cm at ambient temperature. The developed plates were scanned and quantified at a single wavelength of maximum absorption at 360 and 287 nm for CL and GA, respectively. Experimental conditions such as band size, chamber saturation time, migration of solvent front, slit width, etc., were critically studied, and the optimum conditions were selected. The drug samples were satisfactorily resolved with Rf 0.35 ± 0.02 for colchicine and 0.69 ± 0.03 for gallic acid. The method was validated for linearity, accuracy, precision and specificity. The calibration plot was linear between 25 and 200 ng per band for CL and 100–800 ng per band for GA. The limits of detection and quantification for CL were 2.0 and 25.00 ng per band, respectively, whereas for GA, these were 10.00 and 100.00 ng per band, respectively. The proposed HPTLC method for estimation of CL and GA was found to be economic, simple, precise, sensitive and less time consuming than other chromatographic procedures and can be used for routine quality control of Habb-e-Irqun-Nisa and other polyherbal formulations containing these phytoconstituents.  相似文献   
90.
Now‐a‐days, plant species are consumed globally for various purposes and this increasing demand leads to adulteration due to gradually exploitation in natural resources. The major causes of adulteration may be confusion in nomenclature, unawareness of authentic sources, unavailability of authentic sources, color resemblances, deficiencies in collection procedures, and misidentification. This study aims to use the microscopic techniques such as scanning electron microscopy for the authentication of the oil yielding seeds of four important and traditionally used species Prunus persica, Prunus domestica, and Eruca sativa and Argemone Mexicana from their adulterants. All of these are versatile in usage. Locally, these four plants are adulterated badly and there is need to provide a criteria and a complete monograph for correct identification. This research may prove to be helpful for quality control and as well for future studies to explore other novel aspects of these plants.  相似文献   
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