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1.
The objective of this study was to compare methane production and characteristics of digested material in anaerobic digestion concepts according to the Animal By-Products Regulation (ABP-Regulation) of the EC (hygienisation of biowaste for 1 hour at 70 degrees C, particle size < 12 mm) and Finnish national regulations (treatment temperature 55 degrees C, feeding interval 24 h, hydraulic retention time (HRT) 20 d, particle size < 40 mm) and with small variations in treatment methods for treating manure and biowaste. Moreover, the survival of three different salmonella bacteria in these processes was studied. Hygienisation of biowaste prior to digestion at 35 degrees C enhanced methane production by 14-18% compared to similar treatment without hygienisation. The differences in treatment temperature, HRT and hygienisation of biowaste prior to digestion did not significantly affect the characteristics of digested material. The concepts according to the ABP-Regulation and Finnish national regulations were effective in destroying salmonella bacteria to an undetectable level.  相似文献   
2.
In this paper, a micropower interface IC for a capacitive 3-axis micro-accelerometer implemented in a 0.13- BiCMOS process is presented. The sensor interface consists of a front-end that converts the acceleration signal to voltage, two algorithmic ADCs, two frequency references, and a voltage, current, and temperature reference circuit. Die area and power dissipation are reduced by using time-multiplexed sampling and varying duty cycles down to 0.3%. The chip with a 0.51 active area draws 62 from a 1.8 V supply while sampling temperature at 100 Hz, and four proof masses, each at 1.04 kHz. With a 4-g capacitive 3-axis accelerometer, the measured noise floors in the x-, y-, and z-directions are 482 , 639 , and 662 , respectively.  相似文献   
3.
OBJECTIVE: This analysis examines 1-year transition probabilities and baseline predictors for suicidal behaviors in young adolescents. METHOD: Adolescents from a two-stage, community-based longitudinal study were classified into suicidal behavior categories (attempt, plan, ideation, and none) for baseline and follow-up years. Transition probabilities for movement among categories were calculated, and polytomous logistic regression analysis was used to examine predictors of suicidal behaviors. RESULTS: Among those with no suicidal behaviors at baseline, 1-year incidence rates were 1.3% for attempts and 1.7% each for plans and ideation. Increasing family cohesion was protective for suicide attempts (odds ratio [OR] = 0.9). Female subjects were more likely than males to report plans (OR = 8.9) and ideation (OR = 4.1). Increasing impulsivity (OR = 2.3), prior suicidal behavior (OR = 10.6), and undesirable life events (OR = 1.1) were significant predictors of plans. CONCLUSIONS: While there are a number of predictors of suicidal behaviors, the false-positive rate is high. Focusing on proximal risk factors, particularly stressors in adolescent development, may overlook the fundamental role of underlying mental disorder and familial factors--both biological and environmental. Suicide and suicidal behaviors are the result of a constellation of adverse factors requiring a range of interventions for prevention.  相似文献   
4.
QT dispersion is a measure of heterogeneity in ventricular repolarization. Increased ECG QT dispersion is associated with life-threatening ventricular arrhythmias. We studied if magnetocardiographic (MCG) measures of QT dispersion can separate postmyocardial infarction patients with and without susceptibility to sustained VT. Manual dispersion measurements were compared to a newly adapted automatic QT interval analysis method. Ten patients with a history of sustained VT (VT group) and eight patients without ventricular arrhythmias (Controls) were studied after a remote myocardial infarction. Single-channel MCGs were recorded from 42 locations over the frontal chest area and the signals were averaged. QT dispersion was defined as maximum-minimum or standard deviation of measured QT intervals. VT group showed significantly more QT and JT dispersion than Controls. QTapex dispersions were 127 +/- 26 versus 83 +/- 21 ms (P = 0.004) and QTend dispersions 130 +/- 37 versus 82 +/- 37 ms (P = 0.013), respectively. Automatic method gave comparable values. Their relative differences were 9% for QTapex and 27% for QTend dispersion on average. In conclusion, increased MCG QT interval dispersion seems to be associated with a susceptibility to VT in postmyocardial infarction patients. MCG mapping with automated QT interval analysis may provide a user independent method to detect nonhomogeneity in ventricular repolarization.  相似文献   
5.
Summary: Propylene was copolymerized with 10‐undecen‐1‐ol using dimethylsilanylbis(2‐methyl‐4‐phenyl‐1‐indenyl)zirconium dichloride as catalyst and MAO and TIBA as cocatalysts. Comonomer incorporations from 0.1 to 0.9 mol‐% (0.5 to 3.6 wt.‐%) were obtained. These hydroxyl functionalized copolymers were applied as compatibilizers to PP/PA6 blend with a composition of 70/30. For comparison, hydroxyl functionalized polyethylene prepared with metallocene catalyst and commercial MAH grafted ethylene butyl acrylate (E/BA/MAH) and poly(propylene) (PP‐g‐MAH) were also used as compatibilizers. Effects of the compatibilizers on morphology and mechanical and thermal properties of the blends were studied. Enhanced adhesion between the blend components was observed in morphology and dynamic mechanical studies. Although improvement in toughness was not as pronounced as expected, there were indications that the hydroxyl functionalized propylene copolymers prepared with metallocene catalysts could serve as a new type of compatibilizer in polymer blends.

SEM micrograph (5 000×) of an PP/PA6/PP‐co‐OH4 blend.  相似文献   

6.
For purposes of simulating contemporary communication systems, it is, in many cases, useful to apply error models for specific levels of abstraction. Such models should approximate the packet error behavior of a given system at a specific protocol layer, thus incorporating the possible detrimental effects of lower protocol layers. Packet error models can efficiently be realized using finite-state models; for example, there exists a wide range of studies on using Markov models to simulate communication channels. In this paper, we consider aggregated Markov processes, which are a subclass of hidden Markov models (HMMs). Artificial limitations are set on the state transition probabilities of the models to find efficient methods of parameter estimation. We apply these models to the simulation of the performance of digital video broadcasting-handheld (DVB-H). The parameters of the packet error models are approximated as functions of the time-variant received signal strength and speed of a mobile vehicular DVB-H receiver, and it is shown that useful results may be achieved with the described packet error models, particularly when simulating mobile reception in field conditions.  相似文献   
7.
HDL particles can be structurally modified in atherosclerotic disorders associated with low HDL cholesterol level (HDL-C). We studied whether the lipidome of the main phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and sphingomyelin (SM) species of HDL2 and HDL3 subfractions is associated with premature coronary heart disease (CHD) or metabolic syndrome (MetS) in families where common low HDL-C predisposes to premature CHD. The lipidome was analyzed by LC-MS. Lysophosphatidylcholines were depleted of linoleic acid relative to more saturated and shorter-chained acids containing species in MetS compared with non-affected subjects: the ratio of palmitic to linoleic acid was elevated by more than 30%. A minor PC (16:0/16:1) was elevated (28–40%) in MetS. The contents of oleic acid containing PCs were elevated relative to linoleic acid containing PCs in MetS; the ratio of PC (16:0/18:1) to PC (16:0/18:2) was elevated by 11–16%. Certain PC and SM ratios, e.g., PC (18:0/20:3) to PC (16:0/18:2) and a minor SM 36:2 to an abundant SM 34:1, were higher (11–36%) in MetS and CHD. The fatty acid composition of certain LPCs and PCs displayed a characteristic pattern in MetS, enriched with palmitic, palmitoleic or oleic acids relative to linoleic acid. Certain PC and SM ratios related consistently to CHD and MetS.  相似文献   
8.
National policy calls for the placement of comprehensive, customer-oriented, and accessible health and social services programs for America's children and youth. Schools have been targeted as the ideal location for such services. Numerous models of school-based and school-linked programs have been initiated. The role of psychology in these emerging models and programs is highly variable; however, it is an essential service that increasingly is being recognized as necessary in order for schools to address complex and diverse student and staff health needs. In this article, models for the delivery of school health services are profiled. Implications for practitioners who currently work in schools and for psychologists who are not currently working in schools but who are interested in maximizing psychology's contribution to school health services are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Paavola  J. Ipatov  V. 《Electronics letters》2003,39(9):738-740
Binary signatures are constructed for M+N users in N-dimensional signal space. Proposed signatures preserve the minimum Euclidean distance between signals inherent in an N-dimensional orthogonal signal set. They are easily generated with Hadamard matrices, and they can be applied in oversaturated synchronous CDMA systems.  相似文献   
10.
Decreased taste sensitivity may be one of the many factors influencing the poor nutritional status of many patients with chronic renal failure. Several studies examining taste in chronic uremic and hemodialysis (HD) patients indicate decreased sensitivity; continuous ambulatory peritoneal dialysis (CAPD) patients, however, warrant investigation. The aim of this study was to determine if the taste detection threshold for each of the four tastes (sweet, salty, sour and bitter) differs between CAPD patients and age and sex matched controls with normal renal function. The thresholds were determined using Cornsweet's staircase technique for increasing and decreasing stimulus concentration, in which the subject's response determines the next concentration to be tested. A forced-choice design using three samples was used to help minimize bias. The taste detection threshold for the CAPD patients was significantly higher than that of the controls for sodium chloride (salty)(P = 0.001) and quinine (bitter) (P = 0.01). This information may be useful when designing dietary supplements and devising meal plans to help patients consume nutritionally adequate diets.  相似文献   
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