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41.
42.
In this thesis,aiming at the characteristic of operation directing expert systems,we use the state of process characteristic parameter to describe the process condition(state).We propose a solving strategy batal on characteristic model.According to the solving-tree of process condition (state),the present process state can be obtained. An example of application illustrates that this method solves problem quickly and satisfy the real time directing operation. 相似文献
43.
Successful hybridization of sterlet (Acipenser ruthenus) × Siberian sturgeon (Acipenser baeri), sterlet × Russian sturgeon (Acipenser gueldenstaedti) and sterlet × European sturgeon (Acipenser sturio) was carried out for the first time using cryopreserved semen of sturgeon males and sterlet × sterlet crosses as controls. Sperm of all three species was diluted with a cryodiluent composed of 23.4 mM sucrose, 0.25 mM KCl, 30 mM Tris (pH 8.0) and 10% methanol. The samples were frozen in plastic straws in the vapor of liquid nitrogen at the height of 3 cm above the level of nitrogen for 3 min. Following thawing approximately 3000 sterlet eggs were fertilized with six straws of frozen-thawed sperm. The hatching rate with sterlet sperm was 30.6% while the hatching rate of A. ruthenus × A. baeri, A. ruthenus × A. gueldenstaedti and A. ruthenus × A. sturio hybrids was 50, 17.4 and 34%, respectively. Morphometric markers as well as random amplified polymorphic DNA (RAPD) assay was used to verify interspecific hybridization. 相似文献
44.
Silver fir decline was investigated based on changes in spatial distribution of fir, fir abundance in forest stands, dbh (age) structure of fir, and abundance of fir regeneration. The authors used a large-scale approach to study the dynamics of silver fir over nearly 40 years. Based on Silva-SI, a spatial information system, the majority of total forest area in Slovenia was analysed for changes in the distribution of silver fir in the period 1970-2008 using artificial neural networks (ANNs), with respect to site, stand, and forest management variables. Additionally, changes in abundance of silver fir (hereafter fir) in the same period were analysed with a general linear model, while changes in the dbh structure of fir and fir regeneration were analysed with non-parametric tests. Most selected indicators confirmed the hypothesis of fir decline in the period 1970-2008, as evidenced by a reduction in the area of forests with a share of fir in the total growing stock >25% (from 18.9% to 9.5% of total area), a reduction in the share of fir in the growing stock of forest stands (from 17.5% to 7.5%), ageing of the fir population, and a disproportionate share of fir saplings in the total saplings relative to fir's share in the growing stock of forest stands. A 1.5% increase in fir distribution area in the observed period contradicts the decline hypothesis. ANNs showed that the spatiotemporal dynamics of fir was most affected by four variables: forest type, share of fir in the potential natural vegetation, mean annual precipitation, and mean annual temperature. The latter two, together with the growing stock at the start of study period, the degree of connectivity between fir stands, and bedrock type, were significant predictors of decline of fir abundance in forest stands. Significant differences in spatiotemporal dynamics and changes in fir abundance were found between forest types representing a complex of site conditions and past forest management. A further decline of abundance of fir on a large spatial scale in the next decades is expected. Conservation of fir in forest stands will depend mainly on the successful regeneration of fir and sufficient recruitment. 相似文献
45.
R. A. Pandey S. Malhotra A. S. Rajvaidya S. Sharma S. Peshwe V. K. Raman A. S. Bal 《Water, air, and soil pollution》2004,154(1-4):295-311
The gaseous streams containing hydrogen sulphide (H2S) mixed with nitrogen gas (N2) (H2S, 0.00145 mol L-1), H2S mixed with liquefied petroleum gas (LPG) and refinery fuel gas were evaluated, in batch operation, in a bubbled column reactor for desulphurization using ferric sulphate as an oxidant. Further, the ferrous sulphate produced in the process of oxidation is biologically oxidized to ferric sulphate using biomass enriched with Thiobacillus ferrooxidans-JSPR1 in flask culture experiments. In all the cases, the gases were bubbled into the biologically generated ferric sulphate (from ferrous sulphate solution) for the oxidation of H2S. The results indicate that0.00426 mol L-1 of ferric ions are required for reacting with0.00145 mol L-1 of H2S in a gaseous stream containing mixture of N2 and H2S. A concentration of 0.00447 mol L-1 of ferric ions is needed for oxidation of 0.00145 mol L-1 of H2S mixed with LPG. Similarly, the refinery fuel gas containing 0.0031 mol L-1 of H2S requires 0.00428 mol L-1 of ferric ion for effective desulphurization. The ratio of moles of H2S reacted to moles of Fe2+ produced at optimal condition was 0.533, 0.516, 0.510, respectively, for nitrogen mixed H2S, LPG mixed H2S and refinery fuel gas containing H2S. The removal of H2S from these gaseous streams was more than 98%sulphate produced in the process could be biologically oxidized to ferric sulphate with an efficiency of 98%, using shake flask culture experiments. Based on flask culture experiments for biooxidation of commercial ferrous sulphate to generate ferric sulphate, the biokinetic constants viz. yield coefficient y, maximum specific growth rate constant μmax and half saturation rate constant K s were evaluated. The yield coefficient was found to be 0.112 while μmax and K s were observed to be 0.1686 hr-1 and 187.9 mg L-1, respectively. The evaluation of biokinetic constants for bio-oxidation of ferrous sulphate generated during the scrubbing of refinery fuel gas containing H2S indicated the value of μmax and K s as 0.1426 hr-1 and 205 mg L-1, respectively. The value of yield coefficient in this real system was found to be 0.102. 相似文献
46.
Andrej Rodionov Wulf Amelung Ludwig Haumaier Inga Urusevskaja Wolfgang Zech 《植物养料与土壤学杂志》2006,169(3):363-369
Black Mollisols are typically rich in charred organic matter, however, little is known about the zonal distribution of black C (BC) in steppe soils. In this study, we used benzene polycarboxylic acids (BPCA) as specific markers for BC in particle‐size fractions of depth profiles in several zonal soils (Greyzem, Phaeozem, Chernozem, Kastanozem) of the Russian steppe. In addition, liquid‐state 13C‐NMR spectra were obtained on the alkaline‐soluble soil organic matter (SOM). The results showed that both the content and depth distribution of BC varies in the different soil types; the concentration of BC in the bulk top soils being closely related to the aromaticity of the SOM (r2 = 0.98 for the native topsoils, 0.83 for top‐ and subsurface soils). Especially the Chernozems were rich in aromatic SOM, which partly contained more than 17% BC of total C, most of which being allocated in the mineral fractions. Long‐term arable cropping did not reduce the BC contents of the surface soil, though it did promote the enrichment of BC in the silt fractions. The same shift was detected as soil depth increased. We conclude that BC is not fully inert in these soils, but apparently can be preserved in the silt as decomposition of SOM increased, i.e., it accumulates exactly in that fraction, which has been formerly assigned to contain old, aromatic C. 相似文献
47.
Factors associated with the outcome of peritonitis in horses are seldom described. The objectives of this study were to determine the common clinical signs and clinicopathologic findings and to reveal prognostic factors associated with the outcome of peritonitis in equine patients. Data were examined in a retrospective manner in 55 horses diagnosed with and treated for peritonitis. The most common clinical and clinicopathologic findings were tachycardia (94%), increased amount of peritoneal fluid on ultrasound (84%), altered mucous membranes (82%), bacteria noted on the direct smear (67%), hyperfibrinogenaemia (58%) and left shift (40%). The most commonly isolated organism was E. coli (37%). Survival rates were as follow: 78% in the whole study, 81% in the abdominal lavage group, 93% in the medically and 46% in the surgically managed groups. Complications were more common in the non-survivor group (P < 0.001). Initial haematocrit and surgical interventions were strongly associated with non-survival in the multivariate logistic regression model (P = 0.049, OR: 1.07 and P = 0.01, OR: 9.87, respectively). Prognosis of peritonitis without gastrointestinal rupture depends on the initial hydration status, surgical interventions and development of secondary complications, while other clinical and clinicopathologic findings do not appear to correlate with survival. Prospective evaluation of hydration and perfusion parameters and abdominal lavage warrants further investigation. 相似文献
48.
Demeter Z Palade EA Balogh E Jakab C Farkas R Tánczos B Hornok S 《Acta veterinaria Hungarica》2011,59(4):427-432
Here we report a case of canine babesiosis with unusual morphology of the causative agent. A male, seven-week-old Labrador retriever puppy, exhibiting severe anaemia and haemoglobinuria, was presented at the Clinic of Internal Medicine in February 2011. The puppy was euthanised. The most relevant pathological changes were icterus, severe splenomegaly, generalised lymphadenopathy and haemoglobin nephrosis. Samples were collected from various organs for histology within one hour post mortem. Impression smears were also prepared from the spleen after overnight storage at 4 °C. Tissue sections and smears showed the presence of multiple, coccoid intraerythrocytic bodies that measured 1-2 μm and resembled small babesiae. No large piroplasms were seen. DNA was extracted from the spleen, and a conventional PCR was performed for the amplification of a 450-bp region of the 18S rRNA gene of piroplasms. The causative agent was identified as Babesia canis canis, with 99% sequence identity to other European isolates. Sequence identity to B. gibsoni was only 91%. This is the first account to verify that the morphology of the large canine piroplasm, B. canis, can be uniformly small babesia-like post mortem or following the storage of tissue samples. 相似文献
49.
50.