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1.
PURPOSE: Little is known about the developmental effects of high urinary diversion and bladder defunctionalization in infancy. Although clinical experience shows that a poorly functional bladder may result from urinary diversion in infancy, the mechanisms of change and specific bladder wall alterations have not been well characterized. We hypothesized that cyclic filling and emptying are necessary for normal bladder development. To investigate this important question we created a new animal model. MATERIALS AND METHODS: We designed a new method of hemibladder urinary diversion in 3-week-old New Zealand white rabbits. After vertical midline bladder division half of the bladder was formed into a functional reservoir, which remained in continuity with the ipsilateral ureter and urethra. The other bladder half was defunctionalized and isolated from the urine flow by ureteral ligation. Diversion was created for 3, 7, 14 and 28 days. Urodynamic evaluation was done in the functionalized hemibladders and age matched normal rabbit bladders to test the validity of the functionalized hemibladder as an internal control. Functional and defunctionalized hemibladders as well as age matched, nonoperated normal rabbit bladders were weighed, sectioned and stained to demonstrate muscle and connective tissue components. RESULTS: In 22 of the 27 healthy rabbits (81%) good quality diverted and functional bladder specimens were obtained after diversion. Defunctionalized hemibladders grew more slowly than functionalized bladders and normal age matched control bladders. Histological staining of the bladder wall demonstrated increased connective tissue between the muscle bundles within the diverted specimens than in functional bladders. CONCLUSIONS: Our successful model of urinary diversion may be used to study the developmental and histological effects of urinary diversion in the young bladder. Bladder growth and histological appearance are altered when the stimulus of cyclic filling and emptying is removed. Further studies using this model are warranted to define fully bladder changes that result from diversion and investigate the mechanism of the observed changes.  相似文献   
2.
Genital mycoplasmas have been implicated in different neonatal diseases as pneumonia, sepsis and meningitis. This prospective study was conducted to specify their role in these diseases. POPULATION AND METHODS--A pharyngeal or tracheal swab specimen for mycoplasmas culture was obtained from 100 infants admitted consecutively to the Neonatal Care Unit (NCU) during the first 24 hours of life. Mycoplasma culture of blood and cerebrospinal fluid was also performed. Pharyngeal and/or tracheal specimens were collected again on days 5, 15 and 28 if the child was still in the NCU. Mycoplasma hominis (Mh) and Ureaplasma urealyticum (Uu) were identified by culture in a modified Hayflick's medium. RESULTS--Three-hundred and ten pharyngeal or tracheal swabs were obtained (100 on day 0, 89 on day 5, 72 on day 15 and 49 on day 28). Twenty-one infants had one or more positive swabs in the first five days of life (20 on day 0 and one on day 5); those forming the "Myco+" group and the others forming the "Myco-" group. Uu was isolated alone from 20 infants, associated with Mh from one. Both groups were similar for gestational age, birth weight, maternal fever during labor, prolonged rupture of the fetal membranes or chorioamnionitis and for the incidence of acute respiratory distress. There was a statistically significant difference for the route of delivery (chi 2 < 0.02). One blood culture (from 92 performed) was positive for Uu and another positive for Uu and Mh. Both children were cured without any specific mycoplasmacidal therapy. Three children had probable Uu infection and were also cured without specific therapy. CONCLUSIONS--A pharyngeal colonization with genital mycoplasmas is common in the first days of life (21%) but our data do not allow us to conclude that they are accountable for newborn infections.  相似文献   
3.
The search for anomalies in time series by methods of fuzzy logic is further explored. The algorithms DRAS and FLARS underlying these methods are further developed in the form of the algorithm FCARS that is completely based on fuzzy comparisons. Parts 1 and 2 were published in Cybernetics and Systems Analysis, No. 2, 2002 and No. 4, 2003. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 3–18, May–June 2008.  相似文献   
4.
5.
A suite of FORTRAN subroutines/functions to generate data using empirical formulas for physical sputtering of mono-atomic targets for any elemental incident ion (atom), chemical erosion of graphite, Radiation Enhanced Sublimation (RES) of graphite, the number and energy backscattering coefficients for any elemental incident ion (atom) on a compound target and thermal evaporation of graphite is presented. Since chemical erosion, RES and thermal evaporation depend on the surface temperature of graphite, a subroutine implementing the 1-D heat diffusion equation to determine the temperature of any plasma-facing graphite surface is implemented. As an example to illustrate the use of these subroutines/functions, a simple model for the erosion of a plasma-facing surface, consisting of a simple collisionless sheath model, a 1-dimensional steady state heat diffusion model and 0-dimensional steady state particle balance at the target is developed and a sample listing of the program is presented.

Program summary

Title of program: Plasma Surface Interaction Codes (PSIC)Catalog identifier: ADTRProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTRProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputers for which the program has been designed for and others on which it has been tested: Program is designed for any computer with a FORTRAN-77 compiler. It has been tested on a Linux PC with g77, Absoft f77, f90, f95, Fujitsu f95, Lahey f95Operating systems under which the program has been tested: Linux, UNIXProgramming language used: FORTRAN-77Memory required to execute with typical data: Negligible (executable is 178 861 bytes; add to it the memory used by the Fortran library linked to)No. of bits in a word: 16No. of processors used: 1Has the code been vectorized or parallelized?: NoNo. of bytes in distributed program, including test data, etc.: 11 619No. of lines in distributed program, including test data, etc.: 1015Distribution format: tar gzip fileNature of physical problems: 0-D plasma surface interaction model used to demonstrate calls to subroutines for physical sputtering yield, chemical erosion yield of graphite, RES of graphite, backscattering coefficients, thermal evaporation of graphite and 1-D heat diffusion in graphite.Method of solution: Semi-empirical formulas are used for the PSIs and analytical formulas are used for thermal evaporation and 1-D heat diffusion in graphite.Restrictions on the complexity of the problem: All the PSIs (except for the backscattering coefficients) are valid only for a monoatomic target. The heat diffusion solution is not valid for non-uniform plasmas and for targets for which the heat diffusion is not isotropic.Typical running time: Example program takes much less than 0.01 secondUniversal features of the program: None  相似文献   
6.
This article presents a network-controlled approach of user terminal mobility within anIP based WirelessLAN Access Network. In a first part, this article makes a review of the mobility support, on the subject of emergingWLAN technologies asHIPERLAN/2 andIEEE 802.11, on the one hand, and, regardingIP networks as currently studied withinIETF, on the other hand. Both types ofIP mobility protocols are presented, either global mobility protocols such as MobileIP, or local mobility management protocols (micro mobility). In the next part, the overall principles of our mobility management approach are explained; this approach is based on the implementation of a new network entity dedicated to the control of user terminal mobility. The last part details a practical implementation of this approach. The implementation is carried out on the basis of Hierarchical MobileIPv6 (HMIPv6). The experimental results confirm the importance to carefully plan and control the user terminal mobility within largeIP based Access Networks, as this brings benefit to the user as well as to the operator.  相似文献   
7.
Wireless LAN technologies such as IEEE 802.11a and 802.11b support high bandwidth and multi-rate data transmission to match the channel condition (i.e., signal to noise ratio). While some wireless packet fair queuing algorithms to achieve the per-flow throughput fairness have been proposed, they are not appropriate for guaranteeing QoS in multi-rate wireless LAN environments. We propose a wireless packet scheduling algorithm that uses the multi-state (multi-rate) wireless channel model and performs packet scheduling by taking into account the channel usage time of each flow. The proposed algorithm aims at per-flow protection by providing equal channel usage time for each flow. To achieve the per-flow protection, we propose a temporally fair scheduling algorithm called Contention-Aware Temporally fair Scheduling (CATS) which provides equal channel usage time for each flow. Channel usage time is defined as the sum of the packet transmission time and the contention overhead time due to the CSMA/CA mechanism. The CATS algorithm provides per-flow protection in wireless LAN environments where the channel qualities of mobile stations are dynamic over time, and where the packet sizes are application-dependent. We also extend CATS to Decentralized-CATS (D-CATS) to provide per-flow protection in the uplink transmission. Using an NS-2 simulation, we evaluate the fairness property of both CATS and D-CATS in various scenarios. Simulation results show that the throughput of mobile stations with stable link conditions is not degraded by the mobility (or link instability) of other stations or by packet size variations. D-CATS also shows less delay and less delay jitter than FIFO. In addition, since D-CATS can coordinate the number of contending mobile stations, the overall throughput is not degraded as the number of mobile stations increases. This work was supported in part by the Brain Korea 21 project of Ministry of Education and in part by the National Research Laboratory project of Ministry of Science and Technology, 2004, Korea.  相似文献   
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9.
In order to assess the evolution of the confinement properties of clay engineered barriers (EBS) when in contact with metallic canisters containing radioactive wastes, Fe(0)-bentonite interactions need to be assessed. “45 days–80 °C” tests were performed using powdered FoCa7 bentonite and metallic iron. Since one fundamental parameter may be the available quantity of Fe(0), a wide range of Iron/Clay mass ratios (I/C) from 0 to 1/3 is used. The confinement power of clay material results from the swelling properties and the retention capacity. Thus, the major criterion which is chosen to assess the evolution of the confinement properties in this study is the variation of Cation Exchange Capacity (CEC). In parallel, the physico-chemical evolution of bentonite is studied using XRD and EDS-TEM microanalyses. The evolution of the distribution of iron environments is obtained by 57Fe Mössbauer spectroscopy.This study evidences that both kaolinite and smectite from the bentonite are altered into SiAlFe gels when in contact with Fe(0). These gels maturates into Fe-rich di-trioctahedral phyllosilicates, whose composition is bounded by the one of odinite and greenalite in a Fe–M+–4Si diagram when I/C = 1/3. Most of all, it is evidenced that the reaction depends on the available quantity of Fe(0). When the I/C ratio is between 1/30 and 1/7.5, the exchange capacity of FoCa7 bentonite starts decreasing, the consumption of Fe(0) becomes significant, the alteration of smectites occurs and secondary oxides are formed. The crystallization of Fe-rich phyllosilicates is observable when I/C ratio is higher, from a threshold between 1/7.5 and 1/5. Above I/C = 1/3.75, initial iron oxides are strongly consumed and participate in the incorporation of Fe2+ and Fe3+ in gels or new phyllosilicates octahedra.These experimental results were used as input data for the prediction of the long-term evolution of the EBS using Crunch reaction-transport model.  相似文献   
10.
The production of high quality diamond films by microwave plasma assisted CVD, with rapid growth rates and good uniformity over large surfaces, requires perfectly optimized reactors from the microwave design point of view. Most MW plasma assisted CVD reactors used for diamond film deposition work on the resonant cavity principle. The design of such reactors relies on 3 choices: i) choice of a suitable resonant mode (i.e. with an electric field structure conducive to plasma ignition), ii) choice of a MW coupling system to excite the cavity, and iii) choice of a quartz window to delimit a reduced pressure zone inside the cavity, so as to obtain the plasma in front of the substrate [1].In this paper, we present an analysis method for MW plasma reactors relying on EM modelling, which allows for the identification of a resonant mode responsible for plasma ignition, applied to an existing reactor exhibiting plasma instabilities and requiring constant supervision.This analysis method, which can be generalised to any resonant cavity reactor, can describe the device behaviour (shape and location of the plasma, occurrence of instabilities) as a function of the various cavity geometrical configurations and to get a first estimate of the process performance.On the basis of such an analysis, it was possible to propose modifications to the reactor considered in order to improve process stability, and obtain higher growth rates. First growth tests done on diamond mono- and nano-crystalline films show excellent material quality and an increase in growth rate by more than an order of magnitude.  相似文献   
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