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Ecoregional variations of aboveground biomass and stand structure in evergreen broadleaved forests

Journal of Forestry Research 2020年第5期31卷 1713-1722页

作者： Tran Van Do Mamoru Yamamoto Osamu Kozan Vo Dai Hai Phung Dinh Trung nguyen Toan Thang Lai Thanh Hai Vu Thanh Nam Trieu Thai Hung Hoang Van Thang Tran Duc Manh Cao Chi Khiem Vu Tien Lam nguyen quang Hung Tran Hoang Quy Pham quang Tuyen Trinh Ngoc Bon nguyen Thi Thu Phuong Ninh Viet Khuong nguyen Van Tuan Dang Thi Hai Ha Tran Hai Long Dang Van Thuyet Dang Thinh Trieu nguyen Van Thinh Tran Anh Hai Duong quang Trung nguyen Van Bich Dinh Hai Dang Pham Tien Dung nguyen Huy Hoang Le Thi Hanh Phan minh quang nguyen Thi Thuy Huong Hoang Thanh Son nguyen Thanh Son nguyen Thi Van Anh nguyen Thi Hoai Anh Pham Dinh Sam Hoang Thi Nhung Hoang Van Thanh nguyen Huu Thinh Tran Hong Van Ho Trung Luong Bui Kieu Hung Research Institute for Sustainable Humanosphere Kyoto UniversityUjiKyotoJapan Silviculture Research Institute Vietnamese Academy of Forest SciencesNorth Tu LiemHanoiVietnam Center for Southeast Asian Studies Kyoto UniversityKyotoJapan Vietnamese Academy of Forest Sciences North Tu LiemHanoiVietnam Vietnam Administration of Forestry No.2 Ngoc HaBa DinhHanoiVietnam

Biotic and abiotic factors control aboveground biomass(AGB)and the structure of forest *** study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam.A data set of 1731-ha plots from 52 locations in undisturbed old-growth forests was *** results indicate that basal area and AGB are closely correlated with annual precipitation,but not with annual temperature,evaporation or hours of *** area and AGB are positively correlated with trees>30 cm *** areas surveyed(52.6%)in these old-growth forests had AGB of 100–200 Mg ha^-1;5.2%had AGB of 400–500 Mg ha^-1,and 0.6%had AGB of>800 Mg ha^-*** percent of the areas surveyed had stand densities of 300–600 ***^-1,and 64%had basal areas of 20–40 m^2 ha^-*** is an important factor influencing the AGB of old-growth,evergreen broadleaved forests in *** causing the loss of large-diameter trees(e.g.,>100 cm DBH)affects AGB but may not seriously affect stand density.

关键词： Aboveground biomass Carbon storage Climatic variables Ecoregion Edaphic variables Oldgrowth forest

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Combining SnO_(2-x)and g-C_(3)N_(4)nanosheets toward S-scheme heterojunction for high selectivity into green products of NO degradation reaction under visible light

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Journal of Materiomics 2022年第1期8卷 1-8页

作者： Pham Van Viet Thanh-Dat nguyen Dai-Phat Bui Cao minh Thi Faculty of Materials Science and Technology University of ScienceVNU-HCM227 Nguyen Van Cu StreetDistrict 5Ho Chi Minh City700000Viet Nam Vietnam National University-Ho Chi minh City Thu Duc DistrictHo Chi Minh City700000Viet Nam Ho Chi minh City University of Technology(HUTECH) 475A Dien Bien Phu StreetBinh Thanh DistrictHo Chi Minh City700000Viet Nam

NOx emissions cause many negative impacts on the living *** photocatalysis of semiconductors is superior for nitric oxide(NO)degradation due to their low redox *** this report,we combine SnO_(2-x)/g-C_(3)N_(4)heterojunction photocatalyst toward the high selectivity into green products under visible light *** show that SnO_(2-x)/g-C_(3)N_(4)heterojunction degraded 40.8%of NO,which is 1.6 times higher than that of g-C_(3)N_(4).In addition,the selectivity coefficient of SnO_(2-x)/g-C_(3)N_(4)is higher 3 times than both pure SnO_(2-x)and g-C_(3)N_(4).Furthermore,SnO_(2-x)/g-C_(3)N_(4)expresses a superior stability for NO photocatalytic-degradation after five *** scavenger trapping test results,and electron spin resonance(ESR)analysis also provide more understanding of the charge transfer mechanism of ***_(2-x)/g-C_(3)N_(4)heterojunction shows a high removal efficiency of NO gas,making it an up-and-coming environmental treatment candidate.

关键词： G-C_(3)N_(4) NO removal Oxygen vacancies Photocatalysis S-scheme

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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

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An Optimized Algorithm for D2D-MIMO 5G Wireless Networks

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Computers, Materials & Continua 2021年第9期68卷 3029-3044页

作者： Shahid Bashir Imran Khan Fahd NAl-Wesabi Nadhem Nemri Ammar Zahary quang Ngoc nguyen 无 Department of Business Studies Namal UniversityPakistan Department of Electrical Engineering University of Engineering and Technology PeshawarPakistan Department of Computer Science King Khalid UniversityMuhayel AseerKSA Faculty of Computer and IT Sana’a UniversitySana’aYemen Department of Communications and Computer Engineering Faculty of Science and Engineering Waseda University Shinjuku-kuTokyo169-0051Japan

The device-to-device(D2D)networking technology is extended to the conventional cellular network to boost the communication efficiency of the entire network,forming a heterogeneous 5G and beyond(B5G)communication network.D2D communication in a cellular cell will boost the efficiency of the spectrum,increase the ability of the device,and reduce the communication burden of base stations through the sharing of approved cell resources,causing serious interference as *** device-to-device(D2D)networking technology is extended to the conventional cellular network to boost the communication efficiency of the entire network,forming a heterogeneous 5G communication network.D2D communication in a cellular cell will boost the efficiency of the spectrum,increase the ability of the device,and reduce the communication burden of base stations through the sharing of approved cell resources,causing serious interference as *** paper proposes an efficient algorithm to minimize interference,based on the parity of the number of antennas,to resolve this *** primary concept is to generate the cellular connection precoding matrix by minimizing the power of interference from the base station to non-targeted *** through the criterion of maximum SINR,the interference suppression matrix of the cellular connection is ***,by removing intra-interference through linear interference alignment,the maximum degree of freedom is *** results of the simulation show that the proposed algorithm efficiently increases the performance of the spectrum,decreases interference,improves the degrees of freedom and energy efficiency compared to current algorithms.

关键词： 5G and beyond(B5G)networks device-to-device heterogeneous interference multiple-input and multiple-output

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软木塞基碳量子点的水热合成及其生物相融荧光成像应用

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新型炭材料 2022年第3期37卷 595-602页

作者： quang Ngo Khoa Hieu nguyen Ngoc Bao Vo Van Quoc Phuoc Vo Thi Ngoc Le Xuan Diem Doc Luong quang Tri nguyen minh Son Le Vu Truong Son Le Van Thanh Ha Che Thi Cam University of Sciences Hue University77 Nguyen HueHueVietnam Faculty of Environmental and Natural Sciences Duy Tan UniversityDa Nang550000Vietnam Institute for Research and Training in Medicine Biology and PharmacyDuy Tan UniversityDa Nang550000Vietnam University of Agriculture and Forestry Hue University102 Phung HungHueVietnam University of Science and Education The University of Da Nang459 Ton Duc ThangLien ChieuDa NangVietnam

以废弃酒瓶软木塞为原料,采用低成本、简单的水热方法合成碳量子点。通过TEM、FTIR、Raman、UV-Vis、PL光谱对碳量子点的结构和光学性能进行分析表征。结果表明,碳量子点的平均直径为6.2±2.7 nm,PL激发谱和碳量子点表面的官能团有关。... 详细信息

以废弃酒瓶软木塞为原料,采用低成本、简单的水热方法合成碳量子点。通过TEM、FTIR、Raman、UV-Vis、PL光谱对碳量子点的结构和光学性能进行分析表征。结果表明,碳量子点的平均直径为6.2±2.7 nm,PL激发谱和碳量子点表面的官能团有关。用硫酸奎宁作为参考,碳量子点的量子效率为1.54%。将获得的碳量子点应用在骨髓间充质干细胞的细胞生物成像上,发现用碳量子点处理后,骨髓间充质干细胞分别在320~380 nm、450~490 nm和450~490 nm范围显示绿色、黄色和红色荧光,表明了碳量子点在荧光成像领域具有潜在的应用价值。

关键词：碳点水热合成荧光荧光图像废酒瓶塞

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Antidiabetic and antioxidant activities of red seaweed Laurencia dendroidea

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Asian Pacific Journal of Tropical Biomedicine 2019年第12期9卷 501-509页

作者： The Han nguyen Thi Huyen nguyen Van minh nguyen Thi Lan Phuong nguyen Thi Van Anh Tran Anh Duy Do Sang Moo Kim Faculty of Food Technology Nha Trang University02 Nguyen Dinh Chieu StreetNha Trang CityKhanh HoaVietnam Quality Control Department Institute of Vaccines and Medical BiologicalsNha Trang CityKhanh HoaVietnam Faculty of Pharmacy University of Medicine and Pharmacy of Ho Chi Minh City41 Dinh Tien Hoang StreetHo Chi Minh CityVietnam Research Department of Marine Conservation Research Institute for Marine Fisheries224 Le Lai StreetHai Phong CityVietnam Department of Marine Food Science and Technology Gangneung-Wonju National University7 Jukheon-gilGangneung 25457Republic of Korea

Objective:To investigate antidiabetic and antioxidant activities of the extract and fractions from Vietnamese red seaweed Laurencia ***:The seaweed Laurencia dendroidea was extracted by using microwave-assisted extraction method in 80%*** seaweed extract was then fractionated using different solvents(n-hexane,chloroform,ethyl acetate,butanol and water).These obtained fractions were evaluated forα-glucosidase inhibitory and antioxidant *** activities were tested using DPPH,nitric oxide radical scavenging and metal chelating *** enzyme inhibition mode was determined using Lineweaver-Burk *** acidic and thermal stabilities,the ethyl acetate fraction was treated at pH 2.0 and 100℃,*** residual inhibitory activity of the fraction was calculated based on the initial inhibitory *** in vivo antidiabetic activity,mice were divided into four groups,including normal control,diabetic control,diabetic mice treated with ethyl acetate fraction and diabetic mice treated with *** glucose level of treated mice during acute and prolonged treatments was *** evaluate the toxicity of the ethyl acetate fraction,the body weight changes and activities of liver function enzymes(aspartate transaminase,alanine transaminase and gammaglutamyl transferase)were carried ***:The extract of Laurencia dendroidea showed strongα-glucosidase inhibitory and DPPH radical scavenging *** concentrations affected bothα-glucosidase inhibitory and antioxidant activities.A 80%aqueous methanol was the suitable solvent for extraction of enzyme inhibitors and *** solvent fractions,ethyl acetate fraction had the highest inhibitory activities againstα-glucosidase with a mixed type of inhibition and the strongest antioxidant activities,and was stable under acidic and thermal *** ethyl acetate fraction treated diabetic mice significantly reduced blood glucose level compare

关键词： α-Glucosidase inhibitor Antidiabetic Antioxidant Red seaweeds Vietnam

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Propagation Characterization and Analysis for 5G mmWave Through Field Experiments

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Computers, Materials & Continua 2021年第8期68卷 2249-2264页

作者： Faizan Qamar Mhd Nour Hindia Tharek Abd Rahman Rosilah Hassan Kaharudin Dimyati quang Ngoc nguyen Centre for Cyber Security Faculty of Information Science and TechnologyUniversiti Kebangsaan Malaysia(UKM)43600BangiSelangorMalaysia Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya50603Kuala LumpurMalaysia Wireless Communication Centre Faculty of Electrical EngineeringUniversiti Teknologi Malaysia81310SkudaiJohorMalaysia Department of Computer Science and Communications Engineering Faculty of Science and EngineeringWaseda UniversityTokyo169-8050Japan

The 5G network has been intensively investigated to realize the ongoing early deployment stage as an effort to match the exponential growth of the number of connected users and their increasing demands for high throughput,bandwidth with Quality of Service(QoS),and low *** that most of the spectrums below 6 GHz are nearly used up,it is not feasible to employ the traditional spectrum,which is currently in ***,a promising and highly feasible effort to satisfy this insufficient frequency spectrum is to acquire new frequency bands for next-generation mobile *** this end,the primary effort has been focused on utilizing the millimeter-wave(mmWave)as the most promising candidate for the frequency ***,though the mmWave frequency band can fulfill the desired bandwidth requirements,it has been demonstrated to endure several issues like scattering,atmospheric absorption,fading,and especially penetration losses compared to the existing sub-6 GHz frequency ***,it is fundamental to optimize the mmWave band propagation channel to facilitate the practical 5G implementation for the network ***,this study intends to investigate the outdoor channel characteristics of 26,28,36,and 38 GHz frequency bands for the communication infrastructure at the building to the ground floor in both Line of Sight(LOS)and Non-Line of Sight(NLOS)*** experimental campaign has studied the propagation path loss models such as Floating-Intercept(FI)and Close-In(CI)for the building to ground floor environment in LOS and NLOS *** findings obtained from the field experiments clearly show that the CI propagation model delivers much better performance in comparison with the FI model,thanks to its simple setup,accuracy,and precise function.

关键词： 5G mmWave propagation channel path loss channel characterization field experiment

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Combined transarterial chemoembolization and stereotactic body radiation therapy as a bridge therapy to liver transplant for hepatocellular carcinoma

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Hepatoma Research 2020年第8期6卷 36-45页

作者： Bui quang Bieu nguyen Dinh Chau nguyen Xuan Kien Le Van Thanh Vu Van quang Thai Doan Ky nguyen Tien Thinh Mai Hong Bang Department of Radiation Oncology and Radiosurgery Military Central Hospital 108Hanoi 100000Vietnam Department of Hepatobiliary and Pancreatic Surgery Military Central Hospital 108Hanoi 100000Vietnam Department of Gastroenterology and Hepatobiliary Military Central Hospital 108Hanoi 100000Vietnam.

Liver transplant(LT)is the curative treatment for patients with hepatocellular carcinoma(HCC).Bridge therapies are local treatments given to patients on the LT waitlist,to prevent tumor progression and to reduce the dropout *** presentation:We reported a 40-year-old man diagnosed with Barcenola-Clinic Liver Cancer BCLC intermediate stage HCC and Child-Pugh A5 hepatitis B virus cirrhosis who underwent combined bridge therapies to ***,the patient received transarterial chemoembolization(TACE)for two times and showed a partial *** he underwent stereotactic body radiation therapy(SBRT)with a total dose of 45 Gy in 3 *** months later,the tumor size and serum protein induced by Vitamin K absence or antagonists-II,alpha fetoprotein levels decreased *** June 2019 a suitable donor was found and his LT was successfully ***:We propose that a combination of TACE and SBRT was feasible as bridge therapy for HCC patients on the LT waitlist.

关键词： Transarterial chemoembolization stereotactic body radiation therapy bridge therapy hepatocellular carcinoma liver transplant

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A new species of the genus Leptolalax (Anura： Megophryidae) from southern Vietnam

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Zoological Research 2018年第3期39卷 185-201页

作者： Tang Van Duong Dang Trong Do Chung Dac Ngo Truong quang nguyen Nikolay A. Poyarkov Vietnam National Museum of Nature Vietnam Academy of Science and Technology Hanoi Vietnam Department of Vertebrate Zoology Biological FacultyLomonosov Moscow State University Moscow 119234 Russia Faculty of Natural Sciences Phu Yen University Tuy Hoa Phu Yen Vietnam College of Education Hue University Hue Vietnam Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology Hanoi Vietnam Graduate University of Science and Technology Vietnam Academy of Science and Technology Cau Giay Hanoi Vietnam Joint Russian- Vietnamese Tropical Research and Technological Center Nghia Do Cau Giay Hanoi Vietnam

We describe a new species of megophryid frog from Phu Yen Province in southern Vietnam. Leptolalax macrops sp. nov. is distinguished from its congeners by a combination of the following morphological attributes：（1） body size medium （SVL 28.0-29.3 mm in three adult males, 30.3 mm in single adult female）; （2） supra-axillary glands present, creamy white; ventrolateral glands indistinct; （3） tympanum externally distinct; （4） dorsal skin roughly granular with larger tubercles, dermal ridges on dorsum absent; （5） rudimentary webbing present between fingers I-II and I1-111; rudimentary webbing between all toes; fingers and toes without dermal fringes; （6） in life ventral surface greyish-violet with white speckling; （7） supratympanic fold distinct, dark brown in life; （8） iris bicolored, typically golden in upper half, fading to golden green in lower half; （9） tibia short （TbL/SVL 0.44-0.45 in males）; and （10） eyes large and protuberant （ED/SVL 0.15-0.16 in males） From all congeners for which comparable sequences are available, the new species differs markedly in the 16S rRNA mitochondrial gene sequence （P-distance〉5.7%）. The new species is currently known only from montane evergreen tropical forests of Song Hinh District, Phu Yen Province, and M＇Drak District of Dak Lak Province at elevations of 470-630 m a.s.l.. We suggest the new species should be considered as Data Deficient following the IUCN＇s Red List categories. We also report a previously unknownLeptolalax mtDNA lineage from an evergreen tropica forest in the Hoa Thinh District of Phu Yen Province which may also represent an undescribed species.

关键词： Leptolalax macrops sp. nov. Phu YenProvince Dak Lak Province Southern coastal regionof Vietnam

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基于多目标优化算法的汽车高强钢零件冲压过程优化(英文)

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塑性工程学报 2015年第4期22卷 67-73页

作者：张杰阮光明北京科技大学机械工程学院北京100083

高强钢的冲压工艺参数对产品成形质量至关重要。文章研究了冲压工艺参数,如压边力(100kN^500kN)、摩擦系数(0.08~0.12)以及冲压速度(10mm·s-1~90mm·s-1)对产品成形质量的影响。为获得具有良好成形性能的冲压零件,基于中心组合实验设... 详细信息

高强钢的冲压工艺参数对产品成形质量至关重要。文章研究了冲压工艺参数,如压边力(100kN^500kN)、摩擦系数(0.08~0.12)以及冲压速度(10mm·s-1~90mm·s-1)对产品成形质量的影响。为获得具有良好成形性能的冲压零件,基于中心组合实验设计方法设计有限元仿真方案,由此获得不同工况下的成形指标。采用响应面方法,建立优化模型;采用第二代非支配遗传算法(NSGA-II)优化工艺参数,获得帕雷托优化解;基于优化参数进行冲压实验,结果表明,有限元模型预测的成形缺陷符合实际情况。

关键词：高强钢汽车零件冲压响应面法 NSGA-II

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