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Recent advances in the synthesis of 1,1-diarylalkanes by transitionmetal catalysis

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Science China Chemistry 2021年第4期64卷 513-533页

作者： md.belal Zheqi Li Xiuqiang Lu Guoyin Yin The Institute for Advanced Studies Wuhan UniversityWuhan 430072China School of Ocean Science and Biochemistry Engineering Fuqing Branch of Fujian Normal UniversityFuzhou 350300China

1,1-Diaryl moieties are core structures in a wide range of bioactive and pharmaceutical ***-metal catalysis is a convenient approach to accessing these invaluable compounds affording high yields and *** review summarizes 1,1-diarylalkanes synthesis through transition metal *** focus is given to recent developments,such as reductive cross-electrophile couplings,benzylic C–H bond arylation,transformations involving metal migration,asymmetric hydrogenation of 1,1-diarylalkenes and three-component coupling reactions.

关键词： transition metal catalysis 1,1-diarylalkanes

Synergistic Ni/Cu catalyzed migratory arylsilylation of terminal olefins

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Science Bulletin 2021年第6期66卷 570-577,M0004页

作者： Binzhi Zhao Yuqiang Li Haoyang Li mdbelal Lei Zhu Guoyin Yin The Institute for Advanced Studies Wuhan UniversityWuhan 430072China Institute of Biomedical Materials Industry Technology Hubei Engineering UniversityXiaogan 432000China

Synthesis of organosilanes from alkenes is a very important topic owing to their wide applications.A Ni/Cu dual metal-catalyzed arylsilylation of terminal alkenes,featuring migratory selectivity,has been developed.A wide diversity of aliphatic silanes have been prepared from terminal alkenes,aryl halides and Suginome’s *** protocol is highlighted by excellent regioselectivity,mild reaction conditions and good functional group *** addition to benzylic positions,carbon–carbon bonds can also be constructed at allylic *** mechanistic studies suggest that the copper cocatalyst promotes the transmetalation of Suginome’s reagent,and the addition of a Pyr Ox ligand inhibits the formation of side-products from the carbon-Heck ***,studies toward the nature of the Pyr Ox ligand revealed that the steric hindrance of the oxazoline moiety greatly affects the chain–walking process,but not the arylation step.

关键词： Alkene difunctionalization Arylsilylation Synergistic catalysis Regioselectivity Metal migration

Spatial and seasonal distribution of intertidal macrobenthos with their biomass and functional feeding guilds in the Naf River estuary, Bangladesh

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Journal of Oceanology and Limnology 2019年第3期37卷 1010-1023页

作者： md. Abu NOMAN MAMUNUR Rashid M SHAHANUL Islam M. belal HOSSAIN College of Marine & Environmental Science Tianjin University of Science and TechnologyTianjin 300072China Department of Fisheries and Marine Science Noakhali Science and Technology UniversityBangladesh Faculty of Food Engineering and Biotechnology Tianjin University of Science and TechnologyTianjin 300457China

The Naf River estuary is one of the most productive ecological ecosystems in Bangladesh providing an important feeding area for fishes and other aquatic ***,detailed information on macrobenthic communities is rarely available in this *** study focused on the seasonal and spatial variability of macrobenthic community structure with their biomass and functional *** total,fortyseven taxa were identified under nine major groups and seven functional feeding *** macrobenthic taxa,Polychaeta was dominant in both seasons and all over the estuary contributing 60%of total *** mean abundance of macrobenthos was higher during the pre-monsoon(2 972±1 994 inds./m^2)than the monsoon(1 572±361 inds./m^2)being maximum at mid-estuary region and minimum at upper and lower estuary *** the diversity indices,density(P=0.01,P=0.003),the number of taxa(P=0.000 3,P=0.000 9)and Margalef′s Index(P=0.000 4,P=0.001)of macrobenthos were significantly different among stations and ***-Weiner index(P=0.009,P=0.12)and Pielou’s evenness index(P=0.03,P=0.14)had significant differences among stations but not among *** analysis suggested that distribution of macrofauna is strongly influenced by *** the feeding types,carnivorous were found to be dominant at the upper and mid-estuarine regions,and herbivorous were at lower estuarine *** species were dominant in both *** have shown to be the most abundant feeding type in terms of biomass though herbivores were highest during monsoon.

关键词： macrobenthos seasonal variation spatial variation feeding guilds biomass Naf River estuary

Tree species diversity in relation to environmental variables and disturbance gradients in a northeastern forest in Bangladesh

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Journal of Forestry Research 2019年第6期30卷 2143-2150页

作者： md Anwar Hossain Muha Abdullah Al Pavel Kazuhiro Harada Carl Beierkuhnlein Anke Jentsch Mohammad belal Uddin Bangladesh Bank(Central Bank of Bangladesh) Khulna 9100Bangladesh Forest Research Centre(CEF) School of Agriculture(ISA)University of LisbonTapada da Ajuda1349-017 LisbonPortugal Graduate School of Bioagricultural Sciences Nagoya UniversityNagoya 464-8601Japan Department of Biogeography University of Bayreuth95447 BayreuthGermany Department of Disturbance Ecology University of Bayreuth95447 BayreuthGermany Department of Forestry and Environment Science School of Agriculture and Mineral SciencesShahjalal University of Science and TechnologySylhet 3114Bangladesh

Biodiversity has become an issue of global attention because of growing awareness of its importance and its rapid depletion *** of tree species in relation to environmental and disturbance gradients was examined in three managed *** were randomly sampled in a survey of 75 circular plots(radius=13 m)with 5 subplots(radius=1 m).Generalized linear model analysis was used with a Poisson distribution log link function to understand the effects of variables(organic matter,organic carbon,nitrogen,potassium,pH,elevation and disturbance)on tree species *** correspondence analysis was used to explore ecological relationships among *** result found that the stand characteristics was an important influencing factor in the three *** result showed that the variables had a highly positive influence on tree species richness in the three *** ordination,the selected variables governed the richness of tree *** study can help identify the most important factors that drive tree species richness in the three managed forests in Bangladesh and in similar ecosystems and inform forest management decisions for conservation according to ecological importance.

关键词： Richness Disturbance Forest conservation Lawachara National Park Reserve forest

Assessment of heavy metal contamination in the sur?cial sediments from the lower Meghna River estuary, Noakhali coast, Bangladesh

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International Journal of Sediment Research 2021年第3期36卷 384-391页

作者： Mohammad Abdul Momin Siddique Mahfuzur Rahman Shahriar md.Arifur Rahman md.Rubel Hassan Zeenath Fardous Muhammed Alamgir Zaman Chowdhury Mohammad belal Hossain Department of Oceanography Noakhali Science and Technology University Agrochemical and Environmental Research Division Institute of Food and Radiation Biology Atomic Energy Research Establishment 5. Department of Fisheries and Marine Science Noakhali Science and Technology University Department of Environmental Science and Disaster Management Noakhali Science and Technology University University of South Bohemia in Ceske Budejovice Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses Research Institute of Fish Culture and Hydrobiology

Sediment samples were collected from ten selected sites of the lower Meghna River estuary, and six heavy metals were analyzed with Atomic Absorption Spectrophotometry(AAS) to assess the contamination level and the metals’ association with sediment grain size. The current results revealed that the mean concentrations of the studied metals were ranked in descending order of iron(Fe)(1.29 ? 103 mg/kg) > zinc(Zn)(42.41 mg/kg) > lead(Pb)(12.48 mg/kg) > chromium(Cr)(10.59 mg/kg) > copper(Cu)(6.22 mg/kg) > cadmium(Cd)(0.28 mg/kg). The geo-accumulation, contamination, and pollution load indexes suggested that the lower Meghna river estuary was not contaminated by Fe, Zn, Pb, Cr, and *** mean size of the sediment ranged from 28.92 to 126.2 mm, and the Pearson correlation coefficient showed a significant association between Fe and Pb(coefficient of determination, r2? 0.836; p < 0.05),and no significant correlation was found between individual metals and grain size, indicating no or low influence on the metals distribution.

关键词： Metal pollution Pollution load index Grain size Trace metals

Global geoepidemiology of gastrointestinal surgery rates in Crohn’s disease

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1835-1844页

作者： Simcha Weissman Muhammad Aziz Ayrton Bangolo Vignesh K Nagesh Htat Aung Midhun Mathew Lino Garcia Shiva A Chandar Praveena Karamthoti Harinder Bawa Aseel Alshimari Yabets Kejela Nazish Mehdi Chrishanti A Joseph Athri Kodali Rohan Kumar Priya Goyal Sanya Satheesha Fnu Nivedita Nicole Tesoro Tanni Sethi Gurpreet Singh Areej belal Alina Intisar Hirra Khalid Samuel Cornwell Suchith B Suresh Kareem Ahmed Karabo K Marole Om P Anand Rahat B Reshi Tej I Mehta Sameh Elias Joseph D Feuerstein Department of Medicine Hackensack Meridian Health Palisades Medical CenterNorth BergenNJ 07047United States Division of Gastroenterology and Hepatology University of Toledo Medical CenterToledoOH 43614United States Department of Medicine University of WashingtonSeattleWA 98195United States Department of Radiology Johns Hopkins University HospitalBaltimoreMD 21218United States Division of Gastroenterology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215United States

BACKGROUND Data regarding the worldwide gastrointestinal surgery rates in patients with Crohn’s disease(CD)remains *** To systematically review the global variation in the rates of surgery in *** A comprehensive search analysis was performed using multiple electronic databases from inception through July 1,2020,to identify all full text,randomized controlled trials and cohort studies pertaining to gastrointestinal surgery rates in adult patients with *** included continent based demographic data,CD surgery rates over time,as well as the geoepidemiologic variation in CD surgery *** analyses were conducted using *** Twenty-three studies spanning four continents were *** median proportion of persons with CD who underwent gastrointestinal surgery in studies from North America,Europe,Asia,and Oceania were 30%(range:1.7%-62.0%),40%(range:0.6%-74.0%),17%(range:16.0%-43.0%),and 38%*** clear association was found regarding the proportion of patients undergoing gastrointestinal surgery over time in North America(R^(2)=0.035)and Europe(R^(2)=0.100).A moderate,negative association was seen regarding the proportion of patients undergoing gastrointestinal surgery over time(R^(2)=0.520)in *** There appears to be significant inter-continental variation regarding surgery rates in *** evidencebased guidelines accounting for the geographic differences in managing patients with CD is ***,as a paucity of data on surgery rates in CD exists outside the North American and European continents,future studies,particularly in less studied locales,are warranted.

关键词： Gastrointestinal surgery Crohn’s disease Geoepidemiology Inflammatory bowel disease Prevalence

Evaluation of Combined Effect of Micronutrients (ZnSO₄ + Borax) and Fungicides to Control the Purple Blotch Complex of Onion (Allium cepa)

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American Journal of Plant Sciences 2016年第5期7卷 715-723页

作者： Hasan Ali Hosna Ara Chowdhury Nisha md. belal Hossain md. Rafiqul Islam Department of Plant Pathology Sher-e-Bangla Agricultural University Dhaka Bangladesh

Ten different treatments viz. T0 = Control, T1 = Micronutrients (ZnSO4 + Borax), T2 = Rovral 50 WP + Micronutrients, T3 = Dithane M-45 + Micronutrients, T4 = Ridomil Gold + Micronutrients, T5 = Cupravit + Micronutrients, T6 = Rovral 50 WP, T7 = Dithane M-45, T8 = Ridomil Gold and T9 = Cupravit were evaluated against the purple blotch complex disease of onion caused by Alternaria porri and Stemphylium vesicarium in field condition for bulb yield. In lab condition, all the tested chemical fungicides (Rovral 50 WP, Dithane M-45, Ridomil Gold MZ-72 and Cupravit 50 WP) significantly reduced mycelial growth of both pathogens. Among the fungicides, Rovral 50 WP @ 0.2% reduced the highest radial mycelial growth followed by Dithane M-45 @ 0.45% and Ridomil Gold MZ-72 @ 0.2% compared to control. In field experiment, application of Rovral 50 WP @ 0.2% along with micronutrients showed significant effect in reducing disease incidence and severity which significantly increased bulb yield and yield contributing characters.

关键词： Onion Purple Blotch Complex Micronutrients Fungicides

The Activity Concentrations, Radiation Contamination, and Hazards from Wastes and Soil Samples in Nasirabad Industrial Area, Chattogram, Bangladesh

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Journal of Environmental Protection 2020年第10期11卷 767-778页

作者： Mohammed Didarul Alam Mojumder Mahiuddin Ahmed Masud Kamal Mohammad belal Hossen md. Abdur Rashid Department of Physics Chittagong University of Engineering and Technology Chattogram Bangladesh Atomic Energy Centre Chattogram Bangladesh Atomic Energy Commission Chattogram Bangladesh

Soils and other solid wastes from industrial areas of Nasirabad, Chattogram are usually dumped or used for land development. Information about the radioactivity level presented on these soil and wastes enables one to assess any possible radiological hazard to humankind by the use of such materials. A total of 37 (31 soils and 6 solid waste) samples near from different types of industries along four kilometre range were collected. The presence and activity concentrations of naturally occurred radioactive materials (NORM) and anthropogenic radionuclides in the samples were estimated using HPGe detector of 40% relative efficiency. The activity concentration of 226Ra, 232Th and 40K were found to be ranging from 8 ± 2 to 131 ± 18.33 with an average of 21 Bq·kg-1, 10 ± 2.69 to 133 ± 15.96 with an average of 40 Bq·kg-1 and 81 ± 22.68 to 930 ± 260.40 with an average of 449 Bq·kg-1 respectively. Besides this, some hazard indices like, the radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), and the activity concentration index (Iy) were calculated to assess the radiation hazard in this region. The averages of calculated hazard indices were within the normal limits, except the activity concentration index, which shows elevated values. The outcomes of this study could serve as important baseline radiological data for future epidemiological studies and environmental monitoring initiatives in the study area.

关键词： Industrial Contamination Gamma Spectrometry Activity Concentration Hazard Index

Efficacy of Less Toxic Phytochemicals to Prevent the Insect Vector of <i>Mungbean Yellow Mosaic Virus</i>(<i>MYMV</i>)

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American Journal of Plant Sciences 2019年第1期10卷 44-54页

作者： Jesmin Nahar Joly Hosna Ara Chowdhury Abdullah Ali Imtiaz Fatema Begum Hasibur Rahman md. belal Hossain Department of Plant Pathology Sher-e-Bangla Agricultural University Dhaka Bangladesh

Planting material BARI mungbean-5 and two phytochemicals viz. Imitaf, active ingredient imidacloprid and ACmix, active ingredient chloropyriphos (50%) + Cypermethrin (5%) were used in this experiment. In case of Imitaf, the lowest percent disease incidence (10.12% per plant and 3.51% per plot) and severity (7.21%) were recorded in four times spray (T4) at 70 DAS. The highest percent disease incidence (36.50% per plant and 11.37% per plot) and severity (23.33%) were recorded in no spray (T0) at 70 DAS. In case of ACmix, the lowest percent disease incidence (12.21% per plant and 4.21% per plot) and severity (7.53%) were recorded in four times spray (T4) at 70 DAS. The highest percent disease incidence (36.49% per plant and 11.37% per plot) and severity (36.67%) was recorded in T0 at 70 DAS. The highest number of flower, no of pod and yield was found in four times spray (T4) that was higher in Imitaf than ACmix. The highest chlorophyll content was recorded in four times spray (T4) for Imitaf (49.62 μmol·m-2·s-1) and ACmix (56.80 μmol·m-2·s-1), and the lowest chlorophyll content was recorded in T0 for Imitaf (42.01 μmol·m-2·s-1) and ACmix (48.34 μmol·m-2·s-1). However from the results of this experiment it was revealed that Imitaf gave the better performance to control the insect vector (Whitefly) of MYMV with four times spray.

关键词： Mungbean MYMV Whitefly Phytochemicals Bangladesh