2014 Vol. 29, No. 3
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The endophytic fungi in ascocarps of morchella crassipes from different sites were isolated and identified by morphological thechnology combined with sequence analysis of internal transcribed spacer (ITS) regions.The results indicated that the fungal endophytes in M.crassipes were diverse.From 3 sites 16 fungal strains belonging to 14 taxa were isolated and identified.Among which,15 out of the 16 isolates were ascomycetes or their anamorphs,while only 1 isolate (Mortierella alpina) belonged to Zygomycota.Chaetomium fungi were isolated from samples of three origins and Lecanicillium fungicola var.aleophilum was isolated from sporocarps occurring in Mianyang,Sichuan province and Zhengzhou,Henan province,while the other isolates were specific for each sampling.
Applification of enzyme-linked immunosorbent assay (ELISA),immunochromatography (IC),immunomagnetic separation (IMS),enzyme-linked fluorescent immunoassay (ELFIA),chemiluminescence immunoassay (CLIA) as well as immunosensor (IS) in the detection of food safety has been summarized. Moreover,screening and purification of antigens to be detected in food,rational utilization, and sensibility and the unification of the two contradictory aspects of the method need to be resolved.
Soybean protein isolate(SPI) with a moisture content of 60% was thermo-mechanically treated torque rheometer at 30℃ and 90℃ for 2 min,15 min and 30 min respectively,and characterized by Fourier transform infrared (FT-IR) spectroscopy.The results showed that after thermo-mechanical treatments,the symmetrical and asymmetrical stretching of C-H bonds in -CH2 resides became weak and even disappeared the stretching vibration and asymmetrical stretching of C-H bonds drifted to higher position.The α-helix and β-turn decreased accompanying with β-sheet and random coil increased.For that lower moisture content SPI system,the mechanical effect during thermo-mechanical processing may be the major contributor to the transformation of secondary protein structure.
The processing technology of a compound beverage using apple and Rose roxburghii tratt juices was studied.The influences of some stabilizers on the stability of this beverage were also investigated.The results showed that the optimum formula were as follows:fruit juice 20%,sweetener 12 g/100 mL,citric acid 0.5 g/100 mL.The compound stabilizer was composed of 0.05% pectin,0.05% CMC,0.15% xanthan gum.In this way,the stabilizer may achieve better stabilizing effect.Meanwhile under the conditions of homogeneous pressure 25 MPa,temperature 60℃,sterilized at water bath of 90℃ for 10 min,the compound beverage had smooth taste,even texture,nice flavors and colors of apple and Rose roxburghii tratt.
The decolorization conditions of chitin from Antarctic krill shells were studied.According to the comparative experiment,H2O2 was defined as the decolorant.Through single-factor and orthogonal experiment,the optimum decolorization conditions of chitin from Antarctic krill were as follows:the concentration of H2O2 was 12%,the decolorization temperature was 65℃,processing time was 3h and pH was in 8~9.The proven experiment showed that whiteness after decolorization of chitin from Antarctic krill shells could reach above 70 under this condition.
The recent advances in organic synthesis of glucosides from glycosyl halide were summarized, including glycosyl bromide, glycosyl fluoride, glycosyl iodide as glycosyl donors. The advantage of these glycosyl halides as glycosyl donor is that the synthetic product is pure O-glycosides with high yield, mainly for the β-configuration. The disadvantage is the harsh reaction conditions,which are strictly anhydrous,light avoiding, expensive heavy metal salt catalyst and great toxicity. Glycosyl bromide was unstable at room temperature and not easy for long-term preservation. Thus, exploration of novel glycosyl halide derivatives, implementation of stereo-selectively synthesis, exploration of green synthesis conditions, and avoiding the use of heavy metal salts, are the future research direction in this field.
In order to solve the problems such as the difficulty in the utilization of tobacco rods and the louer use rate, the need for more use of the tobacco powder stick.That relationship of petroleum ether extract content, quality of water extract, aroma component and size of tobacco powder were studied.Experiments conducted by mechanically crushing and sieving the tobacco powder stick samples, comparing the proportion of screening material and form, combining with petroleum ether extract content of each substance screening,combining screening to three segments more than 15 projects, 15 to 60 mesh, 60 mesh sieve, each segment to ensure the uniformity of the quality of the screening goods.Then by comparing the three sections of the screening material quality sensory evaluation it was found that the quality of 15 to 60 mesh screening material was the best, followed by 60 mesh screening material, both of which are better than the quality of the tobacco powder stick samples which were not sieved crushed.They may preferably be used in production.
The effect of microwave expansion on the surface functional groups of tobacco stem by conventional stem cutting method was studied.The stem was characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR).The FT-IR result showed that:after microwave treatment,the percentage of surface hydroxyl,carboxyl and -CN increased significantly.There was no significantly different between traditional cut stem and novel cut stem during FT-IR tests.The XPS result showed that phenolic hydroxyl,ether,carboxy were three forms of carbon in microwave expansion stem.The forms of oxygen in all samples were similar,and expanded stem had higher content of hydroxyl than original stem.In addition,there were many nitrogen groups in the surface of the expanded stem molecule.
Useing the ultrasonic extraction-GC-MS method, the paraffin content of these tobaccos were determined and compared which is typical for different varieties and different parts or different varieties in same region or same variety and different regions.The results showed that factors affecting the paraffin content in tobacco were: varieties, location and origin.Different kinds of tobacco alkane content,in which the highest was the aromatic tobacco, followed by the burley tobacco, the lowest content was the flue-cured tobacco.The same kind of tobacco amount of alkane content,in which the upper leaves in tobacco leaf was the largest, followed by central leaf, the alkane content of lower leaf was the lowest.
Reconstituted tobacco containing different proportion of tea,by using the coating method,were mixed to tobacco and produce blended tobacco cigarettes.Cigarette smoke was trapped with the smoking machine,the total particulate matter of the mainstream smoke was collected,the filters which contained particulate matter of the smoke was extracted through the simultaneous and extraction method (SDE),and then analyzed qualitatively and quantitatively using the GC-MS.Compared with the blank control sample,the results showed that the content of harmful components of phenols in cigarette smoke decreased in different degrees,i.e.,the total harmful component of 10% and 12% cigarette samples decreased 37.4% and 36.8% respectively,and its smoking quality was improved.
Aiming at overcoming the weak anti-jamming capability when brushless DC motor of electric vehicle runs under the base speed range,an improved particle swarm optimization(PSO) algorithm was designed,that is,by changing the learning factor and inertia weight to optimize quantitative factors,scale factor and control rules of the fuzzy controller.The simulation results verifid that the algorithm had features of short control time,small overshoot,high anti-interference,so it could made the brushless DC motor achieve stable operation state over a wide speed range.
Combining the design method of parallel coupled microstrip lines with microwave simulation software ADS2009,a bandpass filter was designed for the UWB(ultra wideband) indoor positioning system.By taking advantage of cascading multilevel parallel coupled microstrip lines,some problems of the filter were settled,such as the narrow bandwidth,the bad ripple characteristics and the big insertion loss,etc.The three parameters of height,spacing and length were selected as the object of optimization and simulation of the filter,the measurement results of the material object are as follows:the insertion loss was less than 3 dB,the out band rejection was higher than 10 dB.Comparing the measured results with the simulation results,the design method had the advantages of simple structure and superior performance and met the needs of the UWB indoor positioning system.
Aiming at the low power factor and the pollution of power grid of conventional AC/DC converter,a Boost circuit,of which AC/DC converter was based on MSP430 was designed.The design,adopting monitors voltage and current signal, through the implementation of double closed loop operation MSP430,using the active power factor correction (APFC) technology to produce PWM wave,controlled on-off conversion circuit MOSFET,and at the same time realized the active power factor correction.The test data showed that this conversion circuit could output the stability voltage of 36 V.Load adjustment rate could reach 0.334%,the lowest power factor adjustment could reach above 0.96.It could meet the requirements of the performance index and had higher control precision.
Maximum power point tracking (MPPT) simulation model of photovoltaic power generation system was designed using PSIM software,in MPPT simulation model,the power circuits adopt BUCK converter,the signal detecting circuits measured voltage and current values of photovoltaic cells,the control circuits used dynamic link library (DLL) module to control the power switch module,the compiled DLL files could be linked to PSIM directly.The model could track irradiation and temperature rapidly ,and it had the advantages of modeling simple and quick simulation.
In order to solve the problem that the optical system of laser-guided projectile seeker and back-end processing circuit of laser-guided projectile can not against high overload,the stereoscopic vibration absorber composed of rubber pad and jelly was designed.The structure against high overload was also designed,such as packaging and solidifying the processing circuit.The simulation analysis and experiment validation showed that the design could decrease the impact effectively to 5.1 kg,and the deformation was also acceptable,so the design could meet the requirements of vibration isolation and shock resistance of the system.
The structure of a new type of elevation-azimuth antenna pedestal which is convenient in disassembly or assembly and can be carried by single soldier was studied. Rotary table azimuth rotating pedestal and repeatably assembled pitching turntable were used in order to meet the mass requirement of every part disassembled. While the structure of the antenna pedestal was analyzed by using the finite element method, some joints like screws, pins and flat keys were neglected and the key joints were checked by theoretical formula to ensure its connection strength. The results showed that the structure of the antenna pedestal was reasonable and its mechanical property also met the use requirements.
The influential factors were studied on the stability of crane jib for the increase of strength,at the same time stiffness and buckling resistance decrease in view of a large number of adoption of high strength steel in crawler crane.The jib model was established based on the finite element software ANSYS,the static state and the eigenvalue buckling were analyzed and the nonlinear buckling analysis was carried out on the jib on the basis of eigenvalue buckling mode shape as initial defects.It was found that the wind load and horizontal inertial force influence on the stability of the boom was relatively small,while the deflection force was the main factor that causes the unstability of the jib.
The numerical simulation researches about the process of vibrating screen had been done using the EDM (discrete element method).The relationship of loose and structural parameters based on the concept of density was analyzed.The influence of feeding rate on the laminate based on the concept of the fine particle ratio was analyzed.The result showed,the best parameters are:wire diameter is 0.75 mm,aperture is 0.7 mm,the inclination is 25°;the best feeding rate on best stratification is 4e+04 p/s.
Network authentication client realizes the restrictions of host routing and the control of extension of Internet and Intranet by monitoring the activities of non-binding Internet access network interface cards.A generic penetration gateway method by utilizing the network bridge and NAT service of virtual machines was proposed.The connection of Internet and Intranet can be realized under the network authentication client environment.Moreover, by composing the host with single or double network cards, three host operating systems of Microsoft and three virtual machine systems designed by different companies, various generic penetration gateway schemes can be generated to meet the needs of different applications.So the proposed method is very flexible and practical.
An algorithm for multi-resolution terrain model generation based on quadtree was put forward.This algorithm took elements as view-dependent and terrain relief into the evaluation standards for level of detail and raised appropriate methods to remove cracks in the course of terrain generation according to the law of node partition and rendering.In drawing terrain,optimized display technologies were used such as frustum culling,backface culling,triangle fan and static data storage.Test results showed that this algorithm could rapidly realize the real-time visualization of large-scale terrain.
A calculation method of water distribution network hydraulic was proposed.The nodes flow continuity equation of water distribution system was reconstructed,the reconstructed matrix was decomposed triangularly by a modified Cholesky decomposition method,and thus it was suitable for the use of preconditioned conjugate gradient method.It was tested by the model of water distribution network(WDN) hydraulic.Compared with calculation result of EPANET software,the proposed algorithm does total iteration five times in 0.102 s,which closed to the result of mixed node-ring method used in EPANET software in the aspect of accuracy and speed. The proposed algorithm overcame the defects of EPANET software,which could be used to solve large-scale urban water supply network system.
To monitor the ammonia leak in the process of denitration by using ammonia in thermal power plant,a real-time monitoring system integrated collect data, send alarm signal and query information was proposed using some communication technologies such as GSM, Internet, ZigBee, etc.The wireless sensor network was used to implement distributed monitoring of ammonia leakage in the system of denitration by using ammonia. The system effectively improved the safety of the process of denitration by using ammonia. Moreover, it had some merits such as low power consumption, low cost and flexible networking, etc.
Aiming at the questions that the campus integrated service platform developing in traditional way was difficult to maintain,and extend and the user experience was not good enough, a developing scheme integrated SSH2 and jQuery was proposed using MyEclipse 8.5 as development tool and MySQL.In this scheme, view layer was implemented by the JSP and jQuery framework, business logic layer was implemented by Struts2 and Spring framework, data persistence layer was implemented by Hibernate and Spring Framework. The results showed that the scheme improved the efficiency of the system, enhanced the maintainability and scalability of the system and the user experience.
Using RSA encryption algorithm and symmetric encryption algorithm, the hierarchical encryption algorithm for different levels of information of digital library was proposed.In this algorithm, the core information (first level information) was encrypted and decrypted using RSA, and the inside information (second level information) was encrypted and decrypted using RSA and symmetric algorithm.The first level manager could decrypt the first level information and the second level information, but the second level manager could only decrypt the second level information.None but the first level manager or the second level manager could decrypt.This kind of hierarchical management could not only satisfy the security requirements for different users of digital library, but also facilitate the hierarchical management of different levels of information for digital library.The hierarchical encryption scheme had the availability and effectiveness.
Founded in 1986, bimonthly
Administered by:The Education Department Henan Province
Sponsored by:Zhengzhou University of Light Industry
Editor-in-chief:Wei Shizhong
Executive Editor-in-Chief:Zou Lin
Deputy Editor-in-Chief:Qu Shuanghong
Edited & published by:Editorial Department of Journal of Light Industry
CN 41-1437/TS
ISSN 2096-1553
Address:136 Science Avenue, Zhengzhou City, Henan Province, China
Postal Code:450001
Tel:(086)0371-86608635
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