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81.
Samir Abdulkarim Alharbi Mohammed Asad Kamal Eldin Ahmed Abdelsalam Monjid Ahmed Ibrahim Sunil Chandy 《Molecules (Basel, Switzerland)》2022,27(15)
Boswellia sacra oleo gum resin (Burseraceae) commonly known as frankincense is traditionally used in many countries for its beneficial effect on male fertility. This study explores its effect on the male reproductive system after a 60-day repeated administration at two different doses to rats (in vivo) and on human Leydig cells (in vitro). The methanolic extract of B. sacra was analyzed for the presence of various constituents by preliminary phytochemical analysis and gas chromatography-mass spectrometry (GC-MS) while quantitative analysis of boswellic acids was done by high-performance liquid chromatography (HPLC). Administration of B. sacra extract to rats elevated the serum testosterone levels with an associated reduction in serum levels of FSH and LH. An increase in the activity of antioxidant enzymes, superoxide dismutase and catalase, was seen. A dose-dependent increase in the sperm count and sperm motility was also observed. The in vivo results were supported by changes in the expression of the Bcl-2 gene and caspase-3 gene in human Leydig cells in vitro. The results of this study support the traditional use of B. sacra to increase male fertility. 相似文献
82.
采用激光扫描共聚焦显微镜观察受不同参数高功率微波辐照后的大鼠精子细胞内Ca2+的变化,同时观察了辐照后大鼠的生殖细胞微核率、畸形率、精子数量、存活率和顶体酶反应的变化。实验表明:此条件下的高功率微波辐照对雄性大鼠的生殖细胞微核率和畸形率没有明显的损伤效应,但4×105次脉冲的高功率微波辐照对大鼠的顶体酶反应有较明显的抑制作用,可能通过改变细胞内第二信使的Ca2+浓度来影响其生殖细胞功能。 相似文献
83.
Anna Thoma Ashutosh Dahal Aayush Regmi Alecia Valencia Veronika Viner Rafael Cueto Blane Baker Patrick Bunton John A. Pojman 《Journal of polymer science. Part A, Polymer chemistry》2011,49(19):4261-4266
For the first time, electron paramagnetic resonance spectroscopy was used to compare numbers and distributions of radicals produced in frontal free‐radical polymerization of multifunctional acrylates and methacrylates to those produced by bulk free‐radical polymerization. A comparison of radical concentrations was performed for individual polymers and selected copolymers of trimethylolpropane trimethacrylate (TMPTMA), 1,6‐hexanediol diacrylate, trimethylolpropane triacrylate, and pentaerythritol tetraacrylate (PETA). Frontally polymerized samples showed a large spike in intensity at the point of initiation. Within a few centimeters, the radical signal diminished to a steady state. The radical concentration remained almost constant over 3 months under helium in flame‐sealed tubes. The types of radicals were similar to those in bulk polymerization. For both TMPTMA and PETA, frontally polymerized samples had significantly higher numbers of radicals than did the bulk‐prepared samples, achieving concentrations as high as 8.7 × 10?3 mol/kg in the frontally prepared samples of TMPTMA. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
84.
Guy Wolfovitz 《Random Structures and Algorithms》2011,39(4):539-543
Consider the triangle‐free process, which is defined as follows. Start with G(0), an empty graph on n vertices. Given G(i ‐ 1), let G(i) = G(i ‐ 1) ∪{g(i)}, where g(i) is an edge that is chosen uniformly at random from the set of edges that are not in G(i ? 1) and can be added to G(i ‐ 1) without creating a triangle. The process ends once a maximal triangle‐free graph has been created. Let H be a fixed triangle‐free graph and let XH(i) count the number of copies of H in G(i). We give an asymptotically sharp estimate for ??(XH(i)), for every \begin{align*}1 \ll i \le 2^{-5} n^{3/2} \sqrt{\ln n}\end{align*}, at the limit as n →∞. Moreover, we provide conditions that guarantee that a.a.s. XH(i) = 0, and that XH(i) is concentrated around its mean.© 2011 Wiley Periodicals, Inc. Random Struct. Alg., 2011 相似文献
85.
Sai Chand 《Entropy (Basel, Switzerland)》2021,23(2)
Predictability is important in decision-making in many fields, including transport. The ill-predictability of time-varying processes poses severe problems for traffic and transport planners. The sources of ill-predictability in traffic phenomena could be due to uncertainty and incompleteness of data and models and/or due to the complexity of the processes itself. Traffic counts at intersections are typically consistent and repetitive on the one hand and yet can be less predictable on the other hand, in which on any given time, unusual circumstances such as crashes and adverse weather can dramatically change the traffic condition. Understanding the various causes of high/low predictability in traffic counts is essential for better predictions and the choice of prediction methods. Here, we utilise the Hurst exponent metric from the fractal theory to quantify fluctuations and evaluate the predictability of intersection approach volumes. Data collected from 37 intersections in Sydney, Australia for one year are used. Further, we develop a random-effects linear regression model to quantify the effect of factors such as the day of the week, special event days, public holidays, rainfall, temperature, bus stops, and parking lanes on the predictability of traffic counts. We find that the theoretical predictability of traffic counts at signalised intersections is upwards of 0.80 (i.e., 80%) for most of the days, and the predictability is strongly associated with the day of the week. Public holidays, special event days, and weekends are better predictable than typical weekdays. Rainfall decreases predictability, and intersections with more parking spaces are highly predictable. 相似文献
86.
87.
88.
This paper proposes a statistical method for identifying high‐density regions of pests, so‐called hot spots, within an orchard. Our method uses scanning windows to search for clusters of high counts within the sampled data. The proposed method enables a localized alternative for treatment that could be faster, less costly, and more environmentally friendly. R code that implements the hot spot identification method is provided as online supplementary material. The method is illustrated through simulated examples and a real data on counts of cottony cushion scales from an orchard. 相似文献
89.
Column overloading is very common during the separations of basic analytes in analytical scale reversed-phase liquid chromatography (RPLC). Due to the complex interactions of ionic analytes with stationary and mobile phases, only a very small amount of ionized sample compared to the amount of nonpolar solute can be injected before the peak shape is distorted by non-linear chromatographic processes. Often the amount that can be injected before overload is observed is so small that the signal is quite noisy, thereby making the measured plate count imprecise and possibly inaccurate. The purpose of the present study was to develop a practical method for the precise measurement of the plate count and a column overload parameter using a simple but mathematically rigorous model of Langmuirian non-linear chromatography. An “overload profile”, i.e. a plot of apparent plate count versus amount injected, is characterized by two parameters: the limiting plate count (N0) and the column sample loading capacity (ω0.5). The limiting plate count is the plate count that should be observed when the amount of sample injected is so small that a linear isotherm pertains. The column sample loading capacity, which is taken as the sample load that leads to a plate count equal to half of the limiting plate count, is a measure of the maximum amount of sample that can be injected into that column. The approach was tested by applying it to the study of cationic analytes in RPLC. We show that N0 under constant conditions (column length, flow rate, mobile phase composition, etc.) is almost independent of column type (manufacturer); however, different column types (at the same length, diameter and flow rate) exhibit clear differences in their sample loading capacity (ω0.5). We believe that for most well packed type B columns, the column sample loading capacity and not the limiting plate count is the more important property that accounts for most of the apparent differences in peak width when different types of columns are examined. 相似文献
90.
《Journal of Graph Theory》2018,89(2):150-175
A simple graph is a (2, 1)‐circuit if and for every proper subgraph H of G. Motivated, in part, by ongoing work to understand unique realisations of graphs on surfaces, we derive a constructive characterisation of (2, 1)‐circuits. The characterisation uses the well‐known 1‐extension and X‐replacement operations as well as several summation moves to glue together (2, 1)‐circuits over small cutsets. 相似文献