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Discrete-time sliding mode control with power rate exponential reaching law of a pneumatic artificial muscle system

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Control Theory and Technology 2022年第4期20卷 514-524页

作者： Quy-thinh dao Trung-Kien Le Tri Van-anh Nguyen Manh-Linh Nguyen School of Electrical and Electronic Engineering Hanoi University of Science and TechnologyDai Co VietHanoi 11615Vietnam

this paper develops a discrete-time sliding mode controller with a power rate exponential reaching law approach to enhance the performance of a pneumatic artificial muscle system in both reaching time and chattering *** proposed method dynamically adapts to the variation of the switching function,which is based on an exponential term and a power rate term of the sliding ***,the controlled system can achieve high tracking performance while still obtain chattering-free ***,the effectiveness of the proposed method is validated through multiple experimental tests,focused on a dual pneumatic artificial muscle ***,experimental results show the effectiveness of the proposed approach in this paper.

关键词： Pneumatic artificial muscle Discrete-time sliding mode control Exponential reaching law Chattering

Effect of heating time on structural,morphology,optical,and photocatalytic properties of g-C3N4 nanosheets

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Chinese Physics B 2020年第5期29卷 504-508页

作者： Nguyen Manh Hung Le thi Mai Oanh Lam thi Hang Pham Do Chung Pham thi Duyen dao viet Thang Nguyen Van Minh Center for Nano Science and Technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi100000Vietnam Department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41A Phu Dien RoadNorth Tu LiemHanoi100000Vietnam Hanoi University of Mining and Geology Duc Thang wardNorth Tu Liem DistrictHanoi100000Vietnam Military science Academy 322 Le Trong Tan streetDinh CongHoang MaiHanoi100000Vietnam

Effect of heating time on the structural,morphology,optical,and photocatalytic properties of graphitic carbon nitride(g-C3N4)nanosheets prepared at 550℃in Ar atmosphere is *** investigations are carried out by using x-ray diffraction(XRD),scanning electron microscopy(SEM),Fourier-transform infrared spectroscopy(FTIR),UV-vis absorption,and photoluminescence(PL).At a heating temperature of 550℃,g-C3N4 nanocrystals are formed after 0.5 h and become more orderly as the heating time *** surface area of the g-C3N4 nanosheets significantly increases as the preparation time *** g-C3N4 prepared in 2.5 h shows the highest photocatalytic performance,decomposing completely 10 ppm RhB solution under xenon lamp irradiation for 2.0 h.

关键词： nanosheets photocatalytic heating time Ar atmosphere

Behavior of noncircular tunnels excavated in stratified rock masses-Case of underground coal mines

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 99-110页

作者： Ngoc anh Do Daniel Dias Van Diep Dinh Tien Tung Tran Van Canh dao viet Doan dao Phuc Nhan Nguyen Department of Underground and Mining Construction.Faculty of Civil Engineering Hanoi University of Mining and Ceology School of Automotive and Transportation Engineering Hefei University of Technology Laboratory 35R Crenoble Alpes University

The amount of tunnels excavated along stratified/sedimentary rock masses in Quangninh coal mine area,vietnam, is gradually increasing. Rock mass in Quangninh is characterized by beddings between rock layers. The behavior of stratified rock masses surrounding the tunnels depends on both the intact rock and the beddings between rock layers. The main characteristics of stratified rock masses that need to be considered are their heterogeneity and anisotropy. Depending on the dip angle of rock layers, movements and failure zones developed surrounding the tunnels can be asymmetrical over the vertical axis of tunnel. this asymmetry causes adverse behaviors of the tunnel structures. The objective of this study is to highlight convergences and yielded zones developed in rock masses surrounding noncircular tunnels in Quangninh coal mine area using a finite element method. The presence of bedding joints is explicitly simulated. The numerical results indicated that with the increase in dip angle of bedding joints, the stress asymmetry over the tunnel vertical axis increases. It gradually leads to an asymmetry of the failure zone surrounding the tunnel. An increase of rock mass quality means a decrease of rock mass sensitivity to the discontinuities. In addition,a dip angle of the bedding joints of approximately 45° could be considered as the critical angle at which the rock mass mechanism changes between sliding and bending.

关键词： Tunnel Bedding Stratification Anisotropic Heterogeneity

A method for computing unsupported roof distance in roadway advancement and its in-situ application

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International Journal of Mining Science and Technology 2016年第4期26卷 551-556页

作者： Chen Yong Bai Jianbiao Yan Shuai Hao Shengpeng dao viet Doan State Key Laboratory of Coal Resource and Safe Mining Key Laboratory of Deep Coal Resource Mining Ministry of Education of China China University of Mining and Technology Xuzhou 22116 China Hanoi University of Mining and Geology Hanoi 10000 Viet Nam

A reasonable unsupported roof distance(URD) when advancing underground coal mine roadways can contribute greatly to safe and rapid roadway development.A mechanical model of the roof,using the relationship between the roof stress distribution and URD,obtained by the difference method,and roof stability according to the in-situ roof stress and rock mass strength was *** subsequently designed a proper range of URD,developed a testing method of URD with the function of mining protection,evaluated roof stability through analyzing the test data and then determined a reasonable *** the factors of the geological conditions,the immediate roof stability and the efficiency of the labor arrangement system,the URD of the advancing roadway of 9802 working face in Zhangshuanglou coal mine was determined to be 6 m using the proposed *** results show that,when a 2 m length of roadway was reinforced by temporary support and high pre-stressed bolt support after the roadway advancement of 6 m per cycle,the speed and the security of the roadway development can be achieved and the advance rate can reach more than 400 m per month.

关键词：井下巷道现场应用板间距顶板稳定性计算护顶稳定性评价预应力锚杆

Influence of sintering behavior on the microstructure and electrical properties of BaTiO_(3) lead-free ceramics from hydrothermal synthesized precursor nanoparticles

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Journal of Advanced Dielectrics 2021年第2期11卷 42-51页

作者： Do viet On Le Dai Vuong Truong Van Chuong dao anh Quang Ho Van Tuyen Vo Thanh Tung Department of Physics College of Sciences Hue UniversityHue CityVietnam Faculty of Chemical and Environmental Engineering Hue Industrial College Hue CityVietnam Institute of Research and Development Duy Tan University Da Nang CityVietnam Faculty of Natural Sciences Duy Tan University Da Nang CityVietnam

BaTiO_(3) nanoparticles were synthesized by hydrothermal method using amorphous phase TiO_(2) precursor as the *** microstructure and phase structure were determined using XRD,SEM and Raman spectroscopy analysis *** results showed that BaTiO_(3) nanoparticles have tetragonal structure,average size of about 100 nm was obtained at Ba/Ti ratio of 1.5,synthesis temperature of 200℃ and reaction time of 12 *** components of the BaTiO_(3) lead-free ceramic system are fabricated by conventional solid-phase reaction from the average size BaTiO_(3) particles about 100 nm obtained by hydrothermal *** effects of sintering behavior on dielectric,ferroelectric and piezoelectric properties of BT high-density ceramic were *** BaTiO_(3) ceramic composition sintered at 1300℃ has a relative density of 97%,the value of the electromechanical coefficient kp=0.40,k33=0.42,the large piezoelectric coefficient d_(33)=300 pC/N,d_(31)=−125 pC/N.

关键词： BaTiO_(3)nanoparticles lead-free ceramics piezoelectric ferroelectric properties

One-step hydrothermal synthesis of Sn-doped α-Fe_(2)O_(3) nanoparticles for enhanced photocatalytic degradation of Congo red

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Journal of Semiconductors 2022年第12期43卷 22-31页

作者： Van Nang Lam thi Bich Vu Quang Dat Do thi Thanh Xuan Le Tien Dai Nguyen T-Thanh-Bao Nguyen Hoang Tung Do thi Tu Oanh Nguyen Department of Natural Sciences Hoa Lu UniversityNinh NhatNinh Binh CityViet Nam Institute of Theoretical and Applied Research Duy Tan UniversityHanoi 100000Viet Nam Faculty of Natural Sciences Duy Tan UniversityDa Nang 550000Vietnam Institute of Physics Vietnam Academy of Science and Technology10 Dao TanBa DinhHanoiVietnam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCaugiayHanoiVietnam

We report on the synthesis of Sn-doped hematite nanoparticles(Sn-α-Fe_(2)O_(3) NPs)by the hydrothermal *** prepared Sn-α-Fe_(2)O_(3) NPs had a highly pure and well crystalline rhombohedral phase with an average particle size of 41.4 *** optical properties of as-synthesizedα-Fe_(2)O_(3) NPs show a higher bandgap energy(2.40-2.57 eV)than that of pure bulkα-Fe_(2)O_(3)(2.1 eV).By doping Sn intoα-Fe_(2)O_(3) NPs,the Sn-doped hematite was observed a redshift toward a long wavelength with in-creasing Sn concentration from 0%to 4.0%.The photocatalytic activity of Sn-dopedα-Fe_(2)O_(3) NPs was evaluated by Congo red(CR)dye *** degradation efficiency of CR dye using Sn-α-Fe_(2)O_(3) NPs catalyst is higher than that of pureα-Fe_(2)O_(3) *** highest degradation efficiency of CR dye was 97.8%using 2.5%Sn-dopedα-Fe_(2)O_(3) NPs catalyst under visible-light *** results suggest that the synthesized Sn-dopedα-Fe_(2)O_(3) nanoparticles might be a suitable approach to develop a photocatalytic degradation of toxic inorganic dye in wastewater.

关键词： α-Fe_(2)O_(3)nanoparticles Sn Congo red photocatalytic properties photodegradation

Response of laying hens to L-arginine,L-citrulline and guanidinoacetic acid supplementation in reduced protein diet

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Animal Nutrition 2021年第2期7卷 460-471页

作者： Hiep thi dao Nishchal K.Sharma Emma J.Bradbury Robert A.Swick School of Environmental and Rural Science Faculty of ScienceAgricultureBusiness and LawUniversity of New England2351New South WalesAustralia Faculty of Animal Science Vietnam National University of AgricultureTrau Quy TownGia Lam DistrictHanoiViet Nam Ridley AgriProducts Level 4565 Bourke StreetMelbourneVICAustralia

A study was conducted with Hy-Line Brown laying hens to examine the effects of reduced protein diet,deficiency of arginine(Arg),and addition of crystalline Arg,citrulline(Cit)and guanidinoacetic acid(GAA)as substitutes for *** performance,egg quality,serum uric acid,liver and reproductive organ weights,and energy and protein digestibility were measured using a completely randomized design with 5 *** were a standard diet(17%protein diet;SP),a reduced diet(13%protein diet deficient in Arg;RP)and RP with added Arg(0.35%,RP-Arg),GAA(0.46%equivalent to 0.35%Arg,RP-GAA)or Cit(0.35%,RP-Cit)to the level of *** was hypothesized that performance would decrease with Arg deficient RP diet and the addition of GAA or Cit in RP would allow birds to perform similar or greater than Arg-added RP *** experiment was conducted from 20 to 39 wk of age but the treatment effect was seen only after 29 wk of *** birds offered RP had reduced egg and albumin weights(P0.05).The birds offered RP-GAA decreased FI and egg production(P0.05).However,birds offered the RP-Cit diet tended to have higher Haugh unit(P=0.095)and lower shell breaking strength(P=0.088)compared to all other treatments while those offered RP-GAA had higher energy digestibility(P<0.05)than all other groups but *** limited performance response of hens fed RP with added Arg,GAA,or Cit may be due to deficiency of some other nutrients in RP such as phenylalanine,potassium or non-essential amino acids and other components of soybean meal in the diet.

关键词： Arginine Citrulline Guanidinoacetic acid Laying hen Reduced protein

Effects of L-arginine and L-citrulline supplementation in reduced protein diets for broilers under normal and cyclic warm temperature

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Animal Nutrition 2021年第4期7卷 927-938页

作者： Hiep thi dao Nishchal K.Sharma Emma J.Bradbury Robert A.Swick School of Environmental and Rural Science Faculty of ScienceAgricultureBusiness and LawUniversity of New EnglandArmidaleAustralia Faculty of Animal Science Vietnam National University of AgricultureTrau Quy TownGia Lam DistrictHanoiViet Nam Ridley AgriProducts MelbourneVictoriaAustralia

Heat stress causes significant economic losses in the broiler *** supplementation of arginine(Arg)and citrulline(Cit)might increase the performance of broilers raised under warm temperature due to vasodilation *** study investigated the effects of L-Arg or L-Cit supplementation in broilers fed a reduced protein wheat-based diet deficient in Arg under thermoneutral(NT)and cyclic warm temperature(WT).Ross 308 cockerels(n=720)were randomly allocated to 4 dietary treatments with 12 replicates of 15 birds per pen from d 7 to *** 4 treatments were:normal protein(NP),i.e.,22.3%and 20.9%crude protein in grower and finisher,respectively;reduced protein(RP),i.e.,2.5%lower protein and deficient in Arg;and RP supplemented with 0.28%Arg(RP-Arg)or 0.28%Cit(RP-Cit).A factorial arrangement of treatments was applied during the finisher phase(21 to 35 d).Factors were:diet(4 diets above);and temperature,NT(24℃)or cyclic WT(33±1℃for 6 h per day)with 6 replicate pens per *** 7 to 35 d and 21 to 35 d,the birds fed the RP diet had lower body weight gain(BWG)and higher FCR compared to the NP diet(P0.05)compared to birds exposed to *** by temperature interactions were not observed for performance parameters during the period of WT(P>0.05).On d 35,the RP-fed birds had a lower yield of thigh and drumstick,higher fat pad,lower femur ash,and breaking strength but similar serum uric acid level and higher nitrogen digestibility on d 21 compared to those offered NP(P<0.05).Supplementation of Arg or Cit to RP resulted in increased femur ash on d 35(P<0.05).Thus,feeding the NP diets is necessary to maintain growth performance in broilers regardless of the temperature conditions.

关键词： Arginine Citrulline Meat chickens Low protein Heat stress

Multiparticle^(nat)Sr(γ,xny p)reactions induced with bremsstrahlung end-point energies of 55,60,and 65 MeV

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Chinese Physics C 2022年第9期46卷 185-196页

作者： Nguyen Van Do Nguyen Thanh Luan Nguyen thi Xuan Kim Tien Thanh Nguyen thi Hien Guinyun Kim Institute of Theoretical and Applied Research Duy Tan UniversityHanoi 100000Vietnam Faculty of Natural Sciences Duy Tan UniversityDa Nang 550000Vietnam Institute of Physics Vietnam Academy of Science and Technology10 Dao TanHanoi 10000Vietnam Department of Physics Kyungpook National UniversityDaegu 415661Republic of Korea Graduate School of Science and Technology Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoiVietnam

this study measured the yields of the radionuclides^(82)Sr,^(83(m+g))Sr,^(85m)Sr,^(85g)Sr,^(87m)Sr,^(81(g+0.976m))Rb,^(82m)Rb,^(83g)Rb,^(84(m+g))Rb,and^(86(m+g))Rb produced in^(nat)Sr(γ,xnyp)multiparticle reactions with bremsstrahlung end-point energies of 55,60,and 65 *** bremsstrahlung radiation was generated using the 100-MeV electron linear accelerator at the Pohang Accelerator Laboratory,Korea,and the reaction yields were derived from the induced activitiesmeasured using off-lineγ-ray *** obtain accurate experimental results,we performed the necessaryγ-ray interference *** experimental results were compared with the theoretical predictions obtained using the TALYS-1.95 statistical nuclear model *** calculations were performed using six different level-density models to ascertain which model best fitted the experimental *** dependence of the reaction yield on the incident bremsstrahlung energy and on the number of nucleons emitted by the photonuclear reactions was also investigated.

关键词： reaction yield activation method ^(nat)Sr(γ xnyp)reactions γ-ray spectrometry 55- 60- and 65-MeV bremsstrahlung.