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- Abstract：A new type of small size no-tillage planter was developed to plant small seed crops in the cold, windy and sandy areas of North China where seeding rate was low and weeds control was difficult. The designed machine has the feature of shovel-style opener, squirrel cage type pack roller with the raised rubber bands and the parallel separation of seeds and fertilizer. The planter has the feature of topsoil-tillage, weeding, seeding and fertilizing in the same run. The field tests approved that the variation coefficient of seeding uniformity was about 1.1, the eligible rate of depths for seeds and fertilizer 925%, the eligible rate of the interval between them 857%, and the average successful weeding rate 923% respectively. A roller realized different pressing processes on areas of seed row and inter-rows, after which the fraction of soil clods with diameters of 1-5cm between rows was about 794%, which was propitious to wind erosion control, and 843% for soil clods with diameters of 0-1cm on seed row, which met the requirement of crop growing.Keywords：conservation tillage,shovel-style opener,mechanical weeding,planter0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：Chilocorus rubidus was artificially fed with five types of diets. The results showed that the mixture of grass carp, pig-liver and powder of Noctidae larvae could met the basic nutrition requirement of Chilocorus rubidus adult. The adult fed with the mixture had a high survival rate, but the females had a relatively low egg production. Preying response of Chilocorus rubidus adults on Didesmococcus koreanus was fitted to HollingII model. Adults fed with No.3 and No.5 diets preyed strongly on Didesmococcus koreanus. However, from 25 to 290 days, their preying capacities (1-31 head) decreased with raising duration. Food-seeking efficiency of Chilocorus rubidus (03802- 00717) declined with increasing the densities of Didesmococcus koreauus (2-10 head). A better efficiency was detected in Chilocorus rubidus adults fed with No.3 and No.5 diets. Addiingpreying stimuli in the adult diet could significantly increase the survival rate from winter, egg number of s, preying ability and food-searching efficiency.Keywords：Chilocorus rubidus Hope,artificial diet,feeding stimulus1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The relationship between maturity and aroma quality was studied using flue-cured tobacco leaves in Henan. The results showed that, the contents of major aroma components in tobacco leaves increased with flue-cured tobacco maturity. For example, the concentrations of 3-dimethyl-2-acetylphenol, geranyl-gerandiene, (1S,2E,4R,6R,7E,11S)-2,7,12-duvatrien-4,6-diol, 10-isopropy-3,7,13-trimethyl-2,6,11,13-tetradecnoicen-1-ol, 4,6(E),8(E)-mega- stigmatrienone-3, and tetradecnoic acid reached to maximum at full mature stage of tobacco leaves, and then decreased slowly. The contents of nicotine, palmitic acid, (1S,2E,4R,6R,7E,11S)-2,7,12duvatrien-4,6,11-triol, (1S,2E,4R,6R,7E,11S)-8,11oxygen-2,6,12duvatrien4-ol increased with the leaf maturity and reached to highest levels at over-matured stage. However, the contents of 2-furfural, 2-dimethy-benzaldehyde, 1-ethyl-cyclohexen, 1,2-benzaldehyde -isobutyricbutyrate, 4,6(Z),8(Z)-megastigmatrienone-3 decreased steadily with maturity of tobacco leaves. Our results also showed that full mature tobacco leaves contained high sugar and suitable total nitrogen, nicotine and chemical proportions, with rich and high quality of aroma. The offensive odor and biting taste was low. But both unripe and overripe tobacco leaves had low quality.Keywords：flue-cured tobacco,tobacco leaf,maturity,aroma quality4|2|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：Agropyron cristatum (Wheatgrass) was grown under fertilizer application and treated with row spacing . The data in both 2002 and 2003 indicated that nitrogen (N) was the most important element in Agropyron cristatum seed production. The elements of phosphorus (P) and potassium (K) were also important. Seed yield of Agropyron cristatum increased significantly due to N fertilizer application from 2002 to 2003. The highest yield of 9243kg/hm2 was obtained in the plot with 45cm row spacing, N 45kg/hm2 in autumn and N 90kg/hm2 in spring. N application in both autumn and spring resulted in higher seed yield than only in spring although N quantity was same. The number of fertile tiller was the most important factor in the seed yield formation. It increased significantly with N application in last autumn. Using P fertilizer in spring was benefit to develop fertile tiller, spikelet and seed weight. However, K fertilizer application in spring was in favor of floret, seed number andseed weight. Spikelet, floret, seed number and seed weight of Agropyron cristatum were also improved by thinning row spacing.Keywords：Agropyron cristatum,seed yield,fertile tillers,fertilizer application0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The genetic diversity of 15 concernful domestic chicken breeds in China was studied withusing microsatellite markers. Those chicken breeds included Pudong, Chahua, Langshan, Qingyuan Ma, Dagu, Silky, Xianju, Baier huang, Beijing fattycock, Zang, and the game cocks of Xishuangbanna, Turpan, Zhangzhou, Luxi and Henan. The genetic diversity expressed as mean heterozygosity, mean polymorphic information content (PIC), and Nei standard genetic distances was analyzed by 30 microsatellite markers with high polymorphism. The clustering dendrogram was eventually obtained based on Nei genetic distances of 20 microsatellite. The results showed that the mean heterozygosity in the Turpan was the highest (0634), but lowest (0554)for Henan gamecock. The D_S genetic distances indicated that the differentiation was longer. The UPGMA tree was obtained through analysis of Nei's standard genetic distance (D_S). In the tree, the first group contained Pudong, Chahua, Xishuangbanna gamecock, Zhangzhou gamecock, Dagu, Silky, Xianju, Baier Huang, Beijing fattycock, Henan gamecock, Langshan and Turpan. The second group included Qingyuan spottedcock and Luxi gamecock. Zang had its own branch. UPGMA tree reflected the resource, breeding history, differentiation and direction of utilization. Microsatellite analysis showed that those breeds had rich diversity. The superiorities of the breeds should be explored.Keywords：chicken breeds,microsatellite marker,genetic diversity,genetic distance3|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：Quantitative determination of the transgenic component in soybeans was developed in this study. Based on real-time quantitative PCR technique with SYBR Green I as fluorescent dye combined to double-strand DNA, the endogenous lec gene (encoding soybean lectin) and exotic CaMV35s gene (encoding 35S promotor of CaMV inserted in glyphosate-tolerant soybeans) were amplified. The transgenic ratio was then calculated according to the standard Ct-copies linear graphs of these two genes. The reproducibility and melting curves of the genes were also analyzed. The results showed that the standard equations of lec and CaMV35s genes had higher R2 value of 09997 and 09992 respectively. The difference between the determined and the known transgenic levels of standard and simulated soybeans was only 5%-11%. It was thus suggested that the PCR method with fluorescent dye SYBR Green I was suitable for quantifying the weight ratio of transgenic soybeans in soybean products.Keywords：real-time quantitative PCR,fluorescence dye SYBR Green I,glyphosate-tolerant soybeans,transgenic labeling1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：soybean oil,rumen,fatty acids,sheep4|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：In order to improve the utilization of straws, early indica rices of different varieties with various appending amounts of lactobacillus were appraised for their qualities, in which Lactobacillus was added at the rates of 0001%, 0023% and 0045% respectively and the mixtures were placed into a vacuum-packed polyethylene bags and stored at room temperature for 60d. The results showed that lactobacillus had a remarkable effect on the silage quality without the content of DM and ADL. The CP content increased with the amount of Lactobacillus additive and the CP content of the mixture with 0045% Lactobacillus was 841% higher than the control; however the content of NDF and ADF decreased with the amount of Lactobacillus additive and those of above mixture was 1092% and 1048% lower than the control respectively. The quality of the silage was improved with the lactobacillus addition. The quality of the silage was improved with the lactobacillus addition. The different material also affected silage quality remarkably, but lactic acid content, and the quality of whole-plant Jiayu 948 silage was the best.Keywords：lactobacillus,early indica rice,silage1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：YISHENGKANG (YSK) is a microbial feed additive. A broiler feeding trial was conducted to test the mechanism of YSK in modulating nutrient metabolism and immune function in broiler chickens. The optimum dosage in feed was also studied. Five groups each having 200 broiler chickens were fed with basal diet added with 0, 005%, 01%, 02% YSK and 10mg/kg flavomycin. At 7d and 14d, 05mL beef serum of 5g/L albumin were injected into chicken shin as antigen. The results showed that optimal quantity of YSK was 01%. Comparing with flavomycin, YSK had better effects on promoting chicken growth and enhancing feed efficiency. The growth of thymus gland, spleen and the bursa of Fabricius were all stimulated by YSK. It was found that adding YSK resulted in activity increases of the chicken's T and B lymphocyte, globulin content and antibody level of the serum. YSK could increase the contents of total protein and the globulin in serum through regulating both protein fat metabolisms. The serum lipase activity increased, but the total cholesterol in serum and triglyceride content decreased due to adding YSK. YSK showed significant effects in modulating fat metabolism and lowering down abdominal fat rate (P<005). YSK could obviously depress E. coli, increase Lactobacillus quantity in the jejunum and the rectum, and lower the pH value of chicken gut (P<005). The mechanism of YSK in modulating nutrients metabolism and immune function was included as followings. 1. Some digestive enzymes and acids produced by the microorganisms in YSK could be benefit to both absorption and transformation of the feedstuff2. The microorganisms in YSK might produce vitamin B groups, organic acid and other active materials which enhanced productive performance and growth rate3. YSK might stimulate immune development and adjust gut microfloras. The chicken thus had higher ability against diseases.Keywords：microbial feed additive,Yishengkang,broiler chicken,cellular immunity,humoral immunity,nutrient metabolism,modulating mechanism3|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：breed,Gushi chicks,broiler,meat quality3|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：endothelin-1,BQ123,broiler ascites,pulmonary hypertension0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：In order to manifest the function of the omp-1 in preventing and diagnose of swine (strain cp/12), we cloned and expressed the omp-1 in Ecoli. The gene was amplified by PCR. The specific product was cloned into the pMD18-T Vector. After sequence analysis, it was confirmed to be the target gene. Compared with 4 strains of Chlamydophila abortus in GenBank, the homologies of nucleotide sequences of omp-1 and its putative protein sequence were 99%, but 71%-88% similar with other typical strains of Chlamydia psittaci. The gene was subcloned into pET-32a vector. The recombinant vector was transformed into the host bacteria BL21 (DE3). Induced by IPTG, the bacteria with recombinant vector expressed 58ku fusion proteins. Western-blot analysis showed that the protein could react specifically with Chlamydophila abortus polyclonal antibody.Keywords：swine Chlamydophila abortus,MOMP,clone,expression1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The extracts were obtained from several Chinese medicinal herb of Pulsatilla chinensis, Sophora flavescens, phel lodendron amurense, Radix Astragali and Codonopsis pilosula (Franch) Nannf. Their antidiarrheal effects and mechanisms were investigated. The results showed that the occurrence frequency of diarrhea of piglet was significantly reduced by giving the extracts (P<001 or P<005). Some extracts had significant effect on inhibiting the proliferation of K88 E coli. The diarrhea incidence of mice induced by castor oil or Cassia angustifolia leaf was significantly reduced by feeding extracts (P<001). The acute inflammatory exudation in mouse peritoneum induced by acetic acid was significantly inhibited by some extracts (P<001 or 005), The herb extracts also inhibited alvine movement of mice (P<001). These roles of the Chinese herb extracts on the tested animals might be related to the transport of water and sodium ion from intestinal cavity to the epithelial cells of intestinal mucosa.Keywords：Chinese medicinal herbs,piglet,diarrhea,antidiarrheal mechanism2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：In order to identify the voice activity accurately in a background of 100-115dB high noise, voice signals were interpreted by using a circuit based on the DSPF801 chip produced by the Motorola. The voice detection algorithm used in the circuit could adjust threshold automatically according to the change of noise signals, which ensured a normal communication of the whole system. The test results showed that the detection rate reached 100%, 96% and 94% corresponding the noise levels of 100, 110 and 115dB respectively; and the words loss rate were 2%, 5% and 10% respectively. The system stability reached 100% and 98% respectively in high noise background of 100-110dB and 110-115dB. The system ability on anti-jamming was improved and a precision detection of VD was implemented in a high noise background or to unstable noise signals by the developed algorithm.Keywords：VAD (voice activity detection),short-time energy,zero-cross ratio,short-time auto-correlation,adaptive threshold0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：In this paper a method based on vertical projection was described,because it was difficult to locate crop rows centre lines using computer vision. Firstly, the row crop and background were segmented by the excess green value. Secondly, the image strips were divided by crop image horizontally and the position was calculated by detecting the peak on the curve resulting from vertical projection of strips. Finally, the crop rows center lines were accomplished by robust regression. The experimental results of soybean images, which was 320 pixels width and 240 pixels height, confirmed the effectiveness of this method.Keywords：crop row,centre line,excess green,vertical projection,curve peak2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：Ganoderma lucidum,spore,chitin,hyper high pressure,finite element0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The sub-structure method was used to simulate an aircraft cargo test model and calculate its stress intensity factor (SIF) of cracks in the cargo fuselage. Software for automatic analysis based on ANSYS was developed, which could create a sub-structure of FEM model for the test model and complete the connection of two sub-structures. The SIF was computed from the expanded solution of a sub-structure with crack and a model with 2 substructures. The comparison of the results from the sub-structure method and the whole model method showed that the two calculated results are the similar and close to the experimental results, however, the substructure method takes much less time than that of the other.Keywords：sub-structure,stress intensity factor (SIF),crack,aircraft structure0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：reinforced concrete,cross-section,stress graph0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：dietary fiber,ultra-fine pulverization,particle structure,physical property0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
Preparation of neoglycoprotein from silver carp myofibrillar protein with lactose and its solubility
Keywords：silver carp myofibrillar protein,lactose,myofibrillar glycoprotein,solubility1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22- Abstract：In this paper, a conception of zone feature was put forward. A set of index system about how to appraise the attribute of a geographical unit in the urban fringe was formed comprehensively and systematically and it was composed of fifteen indexes in four aspects, namely, population, economy, society and earth utilization. An appraisal model was built up through the hiberarchy analytical method and the fuzzy appraisal method. Taking Beijing urban fringe as example of this study, the attribute of the four geographical units was appraised, they are the towns of Xiaotangshan, Wenquan, Tanzhesi and Wanliu. The featured attribute values of Xiaotangshan, Wenquan, Tanzhesi and Wanliu are 0.4210, 0.4922, 0.0758 and 0.7116 respectively. The above estimations indicate that Xiaotangshan and Wenquan have the attributes of an outer-fringe of a big city, Wanliu district has the attribute of an inner-fringe of a big city, Tanzhesi the attribute of a rural hinterland, which all are coincident to their real actualities of the geographical units in Beijing. The result shows that this method is feasible and effective.Keywords：urban fringe,zone featured attribute,fuzzy overall evaluation0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：inverted pendulum,pole placement design,PLC,0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：In order to study the geometric non-linear performance of ANSYS, a comparison was made between the finite deformation theory of rod and the geometric non-linear theory of ANSYS Link8 element. An example of the geometric non-linear rod structure was taken to compare the computation results from the finite deformation theory and ANSYS Link8 element. The results showed that the results from the finite deformation theory were more valid than those from ANSYS Link8 element.Keywords：finite deformation,rod element,ANSYS2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：A separated finite element model for mechanical analysis of a reinforced concrete beam (RCB) was established in this paper and a stiffness matrix with 4-node sticking units was deduced. The parameters of vibrational characteristics for healthy and broken RCBs were calculated by the model and the mode parameters of a real RCB were tested. The calculation result proved to be valid. The natural frequency of a RCB is an important indicator to discriminate a RCB is damaged or not. Both the calculated and tested results indicated that the curvature mode shape and the strain mode shape were more sensitive to local damage of a RCB than the displacement mode shape, which enabled them to be used for detection of local damage in a RCB.Keywords：reinforce concrete,structural dynamic analysis,finite element method,modal analysis2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
