• Volume 37,Issue 6,2016 Table of Contents
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    • >Special Column: National Young Scholar/Local Science Foundation
    • Experimental study on manufacturing of grits-spiral-distribution electroplated wire saw

      2016, 37(6):527-532. DOI: 10.7535/hbkd.2016yx06001

      Abstract (1426) HTML (0) PDF 2.13 M (1812) Comment (0) Favorites

      Abstract:In order to obtain high performance electroplating diamond wire saw, experimental studies are conducted for development of grits-spiral-distribution electroplated diamond wire saw using sand-suspend electroplating method. The influences of pre-plating cathode current density, grits electro-embedding cathode current density and time on composite deposite coating appearance and grits distribution of wire saw are analyzed, and the sawing experiment is carried out by using the trial wire saw. The results show that good bonding strength between the coating and the steel wire can be obtained when the adopted cathode current density is 5.0 A/dm2 at pre-plating stage; good coating and girts distribution can be obtained when the adopted cathode current density is 5.0 A/dm2 and the electroplating time is 7~8 min at grits electro-embedding stage. By winding insulation wire on the surface of steel wire and reasonably selecting technological parameters before pre-plating can make the diamond wire saw with grits-spiral-distribution on surface, and the new type of wire saw has a better crumbs-clearing effect in wire sawing process.

    • Design of hydraulic active stabilizer bar test platform based on dSPACE

      2016, 37(6):533-539. DOI: 10.7535/hbkd.2016yx06002

      Abstract (1414) HTML (0) PDF 1.23 M (2969) Comment (0) Favorites

      Abstract:For the study of the influence of hydraulic active stabilizer bar to vehicle lateral stability under high speed steering maneuver, the hydraulic active stabilizer bar HIL test platform is implemented. The HIL test platform is designed with single/double axles universal test bench to experiment on single or double axles active stabilizer bar, using MC9S12DG128 microcontroller as the core controller and running vehicle dynamics model in the dSPACE. This HIL platform is used to study the effect of the hydraulic active stabilizer bar on the vehicle roll stability under different types of the road and typical steering maneuvers. The experiment results illustrate that the hydraulic active stabilizer bar HIL test platform can simulate the experiment environment and provide a powerful support for the development of active stabilizer bar system.

    • Natural characteristics analysis of two teeth difference external compound planet transmission

      2016, 37(6):540-546. DOI: 10.7535/hbkd.2016yx06003

      Abstract (1494) HTML (0) PDF 813.99 K (2651) Comment (0) Favorites

      Abstract:An analytical translational-rotational-coupling dynamic model is developed to evaluate the natural characteristics of two teeth difference external compound planet transmission by adopting centralized parameters method. The governing differential equations are established by deriving relative displacement relationships between all motional components, and Matlab is used to calculate and obtain the natural frequencies and free vibration modes of the transmission system. The analysis results show that the vibration modes are classified into rotational mode of the central members, translational mode of the central members and complicate vibration mode of the planetary gears. The vibration modes are different from the NGW planetary transmission, and especially the planetary gears vibration mode are quite complex with several different vibration modes. The research can provide useful reference for preventing resonance, vibration and noise reduction, and structure optimization of the planet transmission mode used in polishing grinding.

    • Research evaluation of mechanical cutting technology of mulberry branch

      2016, 37(6):547-551. DOI: 10.7535/hbkd.2016yx06004

      Abstract (1560) HTML (0) PDF 821.69 K (2841) Comment (0) Favorites

      Abstract:China is the world's largest silkworm cocoon and raw silk producer and exporter. However, as the labor price increases quickly, the sericulture production costs increases, the comparative benefits of sericulture production decreases, and the farmers' enthusiasm in mulberry planting becomes lower. To solve the problem, aiming at the low level of mechanical harvesting and cutting technology of mulberry branch in China, on the basis of discussing the cutting damage forms of mulberry stool in zhe progress of mechanical harvesting muiberry branch, the existing problems and the present situation of the research of cutting technology of mulberry branch and others crop stalks are analyzed. The developmental trend of the mechanical cutting technology of mulberry branch is put formward.

    • >Mathematics
    • Atom-bond connectivity index and diameter of graphs

      2016, 37(6):552-555. DOI: 10.7535/hbkd.2016yx06005

      Abstract (1822) HTML (0) PDF 372.10 K (2229) Comment (0) Favorites

      Abstract:For further study of the numerous nice properties of topological indices in physical and chemical fields, it is worth considering the relation between a degree-based index and a distance-based index. With the fact that diameter is an invariant based on distance, the relations between atom-bond connectivity index, diameter in trees and unicyclic graphs are studied. Based on relative lemma, the relation between atom-bond connectivity index and diameter in tree and unicyclic graphs is investigated, then the sharp lower bounds of the difference of index and diameter are given.

    • Existence of positive solutions to boundary value problem of second-order three-point difference equations on infinite intervals

      2016, 37(6):556-561. DOI: 10.7535/hbkd.2016yx06006

      Abstract (2139) HTML (0) PDF 513.45 K (1016) Comment (0) Favorites

      Abstract:In order to apply difference equation in boundary value problem on infinite intervals, with the help of the properties of Green function in linear boundary value problems,the boundary value problem of second-order three-point difference equations on infinite intervals is studied. The theory of existence and uniqueness of positive solutions to this problem is are obtained by Banach's contraction mapping principle and Leray-Schauder fixed point theorem, which generalizes the known results.

    • Existence of solutions to boundary value problem of fractional differential equations with impulsive

      2016, 37(6):562-574. DOI: 10.7535/hbkd.2016yx06007

      Abstract (1523) HTML (0) PDF 957.76 K (1263) Comment (0) Favorites

      Abstract:In order to solve the boundary value problem of fractional impulsive differential equations with countable impulses and integral boundary conditions on the half line, the existence of solutions to the boundary problem is specifically studied. By defining suitable Banach spaces, norms and operators, using the properties of fractional calculus and applying the contraction mapping principle and Krasnoselskii's fixed point theorem, the existence of solutions for the boundary value problem of fractional impulsive differential equations with countable impulses and integral boundary conditions on the half line is proved, and examples are given to illustrate the existence of solutions to this kind of equation boundary value problems.

    • Existence of positive solutions to a class of Caputo fractional differential equations

      2016, 37(6):575-580. DOI: 10.7535/hbkd.2016yx06008

      Abstract (2197) HTML (0) PDF 464.14 K (1076) Comment (0) Favorites

      Abstract:In order to investigate the existence of positive solutions to a class of Caputo fractional differential equation boundary value problems with p-Laplacian operator, the Green’s function is obtained by calculus, and its properties are discussed. By using monotone iterative technique, at least two positive solutions are obtained for the boundary value problems. An example is given to illustrate the existence of positive solutions to this kind of equation boundary value problems.

    • >Chemistry and Chemical Industry
    • Quality control method of Polygala telephioides herba

      2016, 37(6):581-586. DOI: 10.7535/hbkd.2016yx06009

      Abstract (1532) HTML (0) PDF 895.62 K (2498) Comment (0) Favorites

      Abstract:In order to control the quality of Polygala telephioides herba, a method is established for the qualitative and quantitative analysis of the herba. Firstly, a TLC method is developed for qualitative detection of Polygala telephioides. Then, with home-made Telephenone B as comparison product and Mangiferin as the reference substance, the relative correlation factor (RCF) of Telephenone B and Mangiferin is determined. The contents are determined by HPLC combined with the quantitative analysis of multi-components by single-marker (QAMS), and the calculated value of QAMS is compared with the measured result to verify the veracity and feasibility of the QAMS method. The results show that the TLC spots are clear and easy to judge. Mangiferin and Telephenone B show good linear relationship in the range of 0.2~1.4 μg (r=0.999 9), 0.13~0.91 μg (r=0.999 4), respectively. The established relative correlation factor shows good reproducibility, and there is no significant difference between the content result calculated by RCF and the content result determined by external standard method. This method is accurate, feasible, and can be used for the quality control of Polygala telephioides herba.

    • Purification of total flavonoids of Abelmoschus manihot (L.) Medic and its antioxidant properties in vivo

      2016, 37(6):587-593. DOI: 10.7535/hbkd.2016yx06010

      Abstract (1740) HTML (0) PDF 1013.92 K (1282) Comment (0) Favorites

      Abstract:In order to optimize the purification conditions and the antioxidant properties in vivo of total flavonoids from Abelmoschus manihot (L.) Medic, AB-8 macroporous resin is used for static adorption and elution. The optimum purification conditions are as follows: Sample solution concerntration of 0.1 g/mL, pH 3.5, 70% ethanol as eluant, 20∶1(mL/g) of eluant volum to resin weight ratio. The results in the optimum purification conditions show that the purity of TFA reaches 48.50%. There are no significant difference in indexes of mice organs between experimental groups and normal control group (P>005). MDA content exhibits a significant decrease both in serum and liver of mice (P<0.05). While the level of CAT, GSH-Px and SOD activities in serum and liver are higher in experimental groups than those in normal control group showing dose-response relationship. These results indicate that TFA has good antioxidant properties in vivo.

    • >Mechanical, Electronics and Information Science
    • Study on torque algorithm of switched reluctance motor

      2016, 37(6):594-600. DOI: 10.7535/hbkd.2016yx06011

      Abstract (1479) HTML (0) PDF 1.11 M (2198) Comment (0) Favorites

      Abstract:To solve the torque ripple problem of switched reluctance motor under the traditional control method, a direct torque control method for switched reluctance motor is proposed. Direct torque algorithm controls flux magnitude and direction by querying appropriate voltage vector in switch list. Taking torque as direct control variable can reduce the torque ripple of the motor, which broadens the application fields of switched reluctance motor. Starting with the theory of direct torque algorithm, based on MATLAB/Simulink platform, direct torque control and chopped current control system simulation model are designed. Under the condition that switched reluctance motor model and its load are consistent, it is compared with chopped current algorithm. At last, the feasibility of direct torque algorithm is verified through the platform of hardware experiments. It demonstrates that using direct torque algorithm can make the torque ripple be controlled effectively, which provides a wider application field for the switched reluctance motor.

    • Design of automatic labeling system on the end surfaces of bundles of round steels

      2016, 37(6):601-608. DOI: 10.7535/hbkd.2016yx06012

      Abstract (1474) HTML (0) PDF 1.47 M (2277) Comment (0) Favorites

      Abstract:To achieve automatic labeling on the end surfaces of bundles of round steels for the steel plants, on the basis of the analysis of round steel production process, a set of automatic system for labeling on the round steel end surfaces of bundles is designed. The system includes the robot visual location unit, the label supply unit, the pressure supply unit, the automatic labeling unit, the laser ranging unit, and the host computer communication control unit, etc.. In the system, the robot visual location unit provides the round steel center location, and the automatic labeling unit implements automatic labeling on the round steel. The system is tested under lab condition, which shows the system can effectively solve the artificial labeling problems such as fault paste and leakage paste of workers, and realize efficient and stable automatic labeling. The system can be used in sleel plants for automatic labeling on the end surfaces of bundles of round steels.

    • >Material Science
    • Influence of forming velocity on the uniformity of microstructure of semisolid die forging 7075 alloy

      2016, 37(6):609-613. DOI: 10.7535/hbkd.2016yx06013

      Abstract (1434) HTML (0) PDF 1.40 M (2533) Comment (0) Favorites

      Abstract:Liquid phase segregation frequently occurs in the process of semi solid die forging, which makes the parts appear "weak point" or "weak region", and usually, the "weak point" or "weak area" is the reason of crack and service condition failure. In order to analyze the influence factors of the liquid phase segregation of the semi solid die forging, DEFORM-3D is used for the numerical simulation of semi-solid die forging forming process of 7075 aluminum alloy, to study the influence rule of forming velocity on the forming process of cup part. Based on the simulation results, the rheological die forging forming of 7075 aluminum alloythe part is conducted to research the influence of forming velocity on the uniformity of microstructure by means of press machine and cup mould. The simulation and experimental results show that as the filling velocity is faster, the forming process is more unstable; under the condition of head temperature of 400 ℃, the forming pressure of 50 MPa, and the alloy temperature 628 ℃, as the forming velocity increases, the liquid phase segregation degree of cup part increases, and the microstructure is far from uniformity. The segregation degree is up to 18.2% as the forming velocity is 5 mm/s.

    • >Civil and Architectural Engineering
    • Form-finding analysis of the tensioned saddle membrane structure considering the cutting lines

      2016, 37(6):614-619. DOI: 10.7535/hbkd.2016yx06014

      Abstract (1420) HTML (0) PDF 968.57 K (2165) Comment (0) Favorites

      Abstract:Traditional membrane structure analysis including form-finding, load analysis and cutting ignores that in practical engineering the membrane structure is with cutting lines which will lead to wrinkle or destruction of the membrane, so the membrane structure with cutting line is designed. The lap joint and similar zero-stress state of the membrane are considered sufficiently during the membrane flatten process. Firstly, the geodesic method is used to generate space tangent line. The sliced space membrane diaphragms are unfolded to produce planar similar zero-stress membrane diaphragms with equivalent plate element method, then, with considering the joints of membrane diaphragms, the planar similar zero-stress membrane diaphragms are joined by thermal connect, and the second forming-finding of the membrane diaphragms is implemented. Finally, the results with and without cutting lines are compared, which proves the effectiveness of the method. The research can provide reference for future design and construction of membranes.

    • >Special Column: New Energy Resources, Energy Conservation and Environmental Protection
    • Design and operation of UASB—A/O process for treatment starch and VB12 wastewater

      2016, 37(6):620-626. DOI: 10.7535/hbkd.2016yx06015

      Abstract (1519) HTML (0) PDF 910.66 K (2227) Comment (0) Favorites

      Abstract:Starch and VB12 wastewater with higher COD and ammonia nitrogen concentration, contains a large number of difficult biodegradable material, complex composition, is difficult to deal with. In recent years, with the increasingly stringent wastewater discharge standards, require the use of a stable and efficient wastewater treatment process for purification treatment of high concentration of ammonia nitrogen in wastewater and the refractory organic pollutants, to achieve discharge standards. Upflow Anaerobic Sludge Blanket (UASB)—Anoxic/Oxic(A/O) process was employed in a wastewater treatment of starch and Vitamin B12 wastewater, which was 5 000 m3/d with highly concentrated organic pollutants and ammonia. The efficiency and reliability of the process has been proven. The results of the system operation show that the concentration of the effluent COD, ammonia and total nitrogen (TN) were at 78.4 mg/L, 18.7 mg/L and 41.1 mg/L, and the treatment efficiencies of COD, ammonia and TN reached over 99%, 92.1%, 82.7%, respectively, when the influent COD and TN concentration were in the ranges of 8 544~9 720 mg/L and 240~250 mg/L. The quality of the treated wastewater met the first-class discharge standards in Integrated Wastewater Discharge Standard(GB 8978—1996).

Editor in chief:朱立光

Inauguration:

International standard number:ISSN 1008-1542

Unified domestic issue:CN 13-1225/TS

Domestic postal code:

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