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One-pot synthesis of silver nanocomposites from Achyranthes aspera:An eco-friendly larvicide against Aedes aegypti L.

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Asian Pacific Journal of Tropical Biomedicine 2020年第2期10卷 54-64页

作者： Aarti Sharma Pushplata Tripathi Sarita Kumar Department of Life Sciences(SOS) Indira Gandhi National Open UniversityMaidan GarhiNew Delhi 110068India Department of Zoology Acharya Narendra Dev CollegeUniversity of DelhiKalkaJiNew Delhi 110019India

Objective:To formulate silver nanocomposites from Achyranthes aspera leaf extracts and evaluate its larvicidal activity against Aedes aegypti.Methods:The silver nanocomposites were synthesized from Achyranthes aspera leaf extracts.The process was optimized and traced through UV-visible and photon correlation spectroscopy.The larvicidal potential of silver nanocomposites of Achyranthes aspera leaf extracts was assessed against the early fourth instars of Aedes aegypti and three non-target organisms.Furthermore,the most effective and eco-safe nanocomposite was characterized by different biophysical techniques including scanning electron microscopy(SEM),energy dispersive X-ray(EDX)spectroscopy,transmission electron microscopy(TEM),X-ray diffraction(XRD)and Fourier transform-infrared spectroscopy(ft-ir).Results:The formulated silver nanocomposites exhibited efficient larvicidal efficacy against Aedes aegypti.Bioassay with silver nanocomposites formulated using different Ag NO3 concentrations(3,4,and 5 m M)revealed respective LC50 values of 37.570,6.262 and 1.041μg/m L;5.819,1.412 and 0.489μg/m L;and 5.519,1.302 and 0.267μg/m L after 24,48 and 72 h.The silver nanocomposites with 4 m M Ag NO3 were selected for characterization.SEM and TEM analysis revealed spherical,poly-dispersed structure with varied diameters of 1-25 nm.The XRD analysis established the crystalline and face-centred-cubic structure of silver nanocomposites with the maximum peak at a 2θvalue of 37.42°.The EDX pattern showed the presence of Ag,O and C in the nanocomposites in their order of weight%.The ft-ir displayed visibly distinct peaks in different ranges demonstrating the intricacy of silver nanocomposites.In addition,the lethal concentrations of silver nanocomposites of Achyranthes aspera leaf extracts against Aedes aegypti larvae were non-toxic to non-target organisms including Gambusia affinis,Daphnia magna and Moina macrocopa.Conclusions:Silver nanocomposites synthesized with leaf extract of Achyranthes aspera provide a cost-effective and eco-

关键词： Achyranthes aspera Aedes aegypti Larvicidal Silver nanocomposites SEM-TEM EDX XRD ft-ir

Biochar characterization of invasive Pennisetum purpureum grass:effect of pyrolysis temperature

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Biochar 2020年第2期2卷 239-251页

作者： Md Sumon Reza Shammya Afroze Muhammad S.A.Bakar Rahman Saidur Navid Aslfattahi Juntakan Taweekun Abul K.Azad Faculty of Integrated Technologies Universiti Brunei DarussalamJalan Tungku LinkGadong BE1410Brunei Darussalam Research Center for Nano-Materials and Energy Technology(RCNMET) School of Science and TechnologySunway UniversityBandar SunwayDarul Ehsan47500 Petaling JayaSelangorMalaysia Department of Mechanical Engineering Faculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Department of Mechanical Engineering Faculty of EngineeringPrince of Songkla UniversityHatyai 90112SongkhlaThailand

Pennisetum purpureum is one of the most invasive perennial grasses of the Poaceae family,which are abundant in south-east Asia including Brunei Darussalam.The pyrolysis process at a slow heating rate proved to be highly promising for biochar production.The production and characterization of different Pennisetum purpureum biochars have been investigated at the pyrolysis temperatures of 400℃,500℃and 600℃with a heating and nitrogen flow rate of 5℃/min and 0.5 L/min,respec-tively.The observed higher heating values were 22.18 MJ/kg,23.02 MJ/kg,23.75 MJ/kg,and the alkaline pH were 9.10,9.86,10.17 for the biochar at 400℃,500℃,600℃temperatures,respectively.The water holding capacity was one hundred percent for all biochars and continued to increase for higher pyrolysis temperature.SEM images show that the porosity of the biochars has been enhanced with increased temperatures due to the rearrangement of crystallinity and aromaticity.On the other hand,the yields of biochar have been decreased from 35.13%to 23.02%for the increase of pyrolysis temperature from 400℃to 600℃.Energy dispersive X-ray analysis shows that the O/C atomic ratios were 0.15,0.08 and 0.06 for the biochar of 400,500 and 600℃which validates the improvement in heating values.ft-ir analysis revealed that the available functional groups in the biochars were C-O,C=C,and C-H.Thermogravimetric analysis(TGA)under pyrolysis condi-tion showed residue of 46.56%,51.13%and 55.67%from the biochar at 400,500,and 600℃,respectively.The derivative thermogravimetry(DTG)graph indicates that the degradation rate is higher for 400℃biochar than the 600℃biochar.

关键词： Pennisetum purpureum Invasive Species Biochar SEM-EDX ft-ir TGA-DTG

In vitro antioxidant and anti-cancer activities and phytochemical analysis of Commelina benghalensis L. root extracts

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Asian Pacific Journal of Tropical Biomedicine 2020年第9期10卷 417-425页

作者： Riffat Batool Ejaz Aziz Javed Iqbal Hina Salahuddin Benny Kwong-Huat Tan Saira Tabassum Tariq Mahmood University Institute of Biochemistry and Biotechnology PMAS-UAAR RawalpindiPakistan Department of Botany GDC KhanpurHaripur Pakistan Department of Plant Sciences Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabad-45320Pakistan Department of Zoology University of OkaraOkaraPakistan Department of Pharmacology Yong Loo Lin School of MedicineNational University of SingaporeSingapore Department of Biotechnology Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabad-45320Pakistan

Objective:To explore antioxidant potential,anti-cancer activity,and phytochemicals of Commelina benghalensis L.Methods:The roots of Commelina benghalensis were extracted in different solvents(methanol,ethanol,benzene,chloroform,n-hexane)with a range of polarity.Antioxidant activity was evaluated by reducing power assay,DPPH radical scavenging activity and phosphomolybdenum method,cytotoxicity by MTT assay,apoptotic and cell cycle analysis by flow cytometry,migratory and invasive potential by wound scratch assay and invasion assay,respectively,functional groups analysis by ft-ir spectroscopy and phytochemicals by aluminum chloride colorimetric and FolinCiocalteu methods.Results:The extracts showed worthy antioxidant potential.The chloroform extract demonstrated the most significant cytotoxic effect on MDA-MB-231(breast cancer)cell line,induced apoptosis and reduced migratory and invasive potential of MDA-MB-231 cells.Methanol and ethanol extracts presented good yield of total phenolic and total flavonoid contents.The ftir spectroscopic studies revealed different characteristic peak values with various functional compounds such as alkenes,alkanes,aliphatic amines,aromatics,alkyl halides,carboxylic acid,alcohols,ester,aldehydes and ketones.Conclusions:The results demonstrate the potential use of Commelina benghalensis as a good antioxidant with significant anticancer effect.

关键词： Commelina benghalensis Anti-cancer Antioxidant ft-ir

Apple Pectin Behavior Separated by Ultrafiltration

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Agricultural Sciences in China 2009年第10期8卷 1193-1202页

作者： QIU Nong-xue TIAN Yu-xia QIAO Shu-tao DENG Hong College of Food Engineering and Nutrientional Science Shaanxi Normal University Xi＇an 710062 P.R. China College of Mechanical Instrument Engineering Xi ＇an University of Technology Xi＇an 710048 P.R. China

Separation conditions of ultrafiltration for apple pectin, weights and their structures and properties are studied and relations between apple pectin with different relative molecular Five kinds of ultrafiltration membranes with different molecular weight cut-offs are used to separate apple pectin. ft-ir and HPGC are used individually to determine the structures and monosaccharide composition of apple pectin with different relative molecular weights. In the case of transmembrane pressure difference of 0.08 MPa, material concentration of 1 g·L^-1, and temperature of 50℃, 6 kinds of apple pectins with different molecular weights have been obtained. Molecular weight of apple pectin is correspondingly related to its physicochemical properties. The galacturonic acid contents and esterification and gelatination degrees increase relatively with an increase in molecular weight, and the monosaccharide composition relatively increase much more. And at the same time, the ultrafiltration has a better role to play in decoloring apple pectin solution. Accordingly, this research can be used as a new method for in-depth exploration of apple pectin.

关键词： apple pectin ultrafiltration ft-ir GC

Application of Modified Attapulgite Clay as the Adsorbent in Gasoline Desulfurization

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China Petroleum Processing & Petrochemical Technology 2014年第3期16卷 63-68页

作者： Xi Xinguo Zhang Jiling Jiang Ruiyu Xu Qi School of Materials Engineering Yancheng Institute of Technology East-China Design Branch China Petroleum Engineering Construction Company Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of Technology School of Chemical and Biological Engineering Yancheng Institute of Technology

Attapulgite clay is a kind of special silicate mineral with high adsorption capacity thanks to its loose structure and porous surface. In this paper, the attapulgite clay was treated effectively with acid under microwave thermal activation and ultrasonic vibration, respectively, and characterized by XRD, N2 adsorption, ft-ir and SEM. The desulfurization performance of the modified attapulgite clay was then evaluated by using simulated gasoline as the feed. The test results showed that the thiophene removal rate increased with an increasing dosage of hydrochloric acid during microwave modification of attapulgite clay. When the concentration of hydrochloric acid reached 15%, the increase of desulfurization rate became slower, and the desulfurization rate was about 69%.

关键词：凹凸棒石粘土汽油脱硫改性应用吸附能力硅酸盐矿物 ft-ir 振动处理

Solid Acid Used as Highly Efficient Catalyst for Esterification of Free Fatty Acids with Alcohols

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China Petroleum Processing & Petrochemical Technology 2013年第1期15卷 19-24页

作者： Zhang Qiuyun Li Hu Qin Wenting Liu Xiaofang Zhang Yuping Xue Wei Yang Song State-Local Joint Laboratory for Comprehensive Utilization of Biomass State Key Laboratory Breeding Base of Green Pesticides and Agricultural BioengineeringCenter for Research and Development of Fine ChemicalsGuizhou University

Anovel solid acid catalyst, which was prepared from sodium alginate (SA) and metal chlorides and characterized with XRD and ft-ir spectrometry, was used for the preparation of biodiesel via esterification reaction. The study results showed that the aluminum-alginate complex prepared in a cheap and easy way exhibited high catalytic activity, and a 92.6% conversion of methyl oleate was obtained in the presence of 4m% of catalyst dosage upon refluxing for 3h of methanol and acid mixed in a molar ratio of 10:1. It should be noted that the catalyst can be applied to the esterification reaction of fatty acids with various carbon chain length on methanol or different short chain alcohols, indicating that the catalyst is suitable for the preparation of biodiesel from waste oils with a high acid value.

关键词：固体酸催化剂高效催化剂游离脂肪酸酯化反应甲醇生物柴油金属氯化物 ft-ir

Structural Characterization of Lignins Isolated from Caragana sinica Using ft-ir and NMR Spectroscopy

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光谱学与光谱分析 2011年第9期31卷 2369-2376页

作者： XIAO Ling-ping SHI Zheng-jun XU Feng SUN Run-cang Amar K Mohanty College of Material Science and Technology Beijing Forestry University Beijing 100083 China State Key Laboratory of Pulp and Paper Engineering South China University of Technology Guangzhou 510640 China Department of Plant Agriculture Bioproducts Discovery and Development Centre (BDDC)University of Guelph Guelph Ontario N1G 2Wl Canada

In order to efficiently explore and use woody biomass,six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions.The lignin structures were characterized by Fourier transform infrared spectroscopy(ft-ir) and 1D and 2D Nuclear Magnetic Resonance(NMR).ft-ir spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.The results of 1H and 13C NMR demonstrated that the lignin fraction L2,isolated with 70% ethanol containing 1% NaOH,was mainly composed of β-O-4 ether bonds together with G and S units and trace p-hydroxyphenyl unit.Based on the 2D HSQC NMR spectrum,the ethanol organosolv lignin fraction L1,extracted with 70% ethanol,presents a predominance of β-O-4′ aryl ether linkages(61% of total side chains),and a low abundance of condensed carbon-carbon linked structures(such as ββ′,β-1′,and β-5′) and a lower S/G ratio.Furthermore,a small percentage(ca.9%) of the linkage side chain was found to be acylated at the γ-carbon.

关键词： Caragana sinica Lignin Structural characterization ft-ir NMR

Spectral Transmittance of Di-methyl Silicon Oil as a Heat Transfer Material for Concentrator Solar Cells

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Transactions of Tianjin University 2015年第5期21卷 453-460页

作者：张博阳王一平黄群武冯加和崔勇 School of Chemical Engineering and Technology Tianjin University Tianjin University Research Institute of Architectural Design & Urban Planning

The accelerated life test was carried out to investigate the change of spectral transmittance of di-methyl silicon oil and the effects on the electrical performance of silicon solar cell. The di-methyl silicon oil samples before and after accelerated life test were analyzed by ft-ir, GC-MS and LC-MS. The ring compounds and linear compounds with larger molecular weight were detected. The spectral transmittance of di-methyl silicon oil decreased because the chromophore and auxochrome of the products made a sunlight receive decrease on the surface of the solar cell, and resulted in the reduction of cell performance. According to the decrease of spectral transmittance of di-methyl silicon oil, two recovery methods were proposed. The results showed that extraction was superior to vacuum distillation in recovering the aged di-methyl silicon oil.

关键词：硅太阳能电池二甲基硅油光谱透过率换热材料加速寿命试验光谱透射率聚光 ft-ir

Vibration spectroscopic technique for species identification based on lipid characteristics

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International Journal of Agricultural and Biological Engineering 2017年第3期10卷 255-268页

作者： Gao Fei Han Lujia Liu Xian Biomass and Bioresource Utilization Laboratory College of EngineeringChina Agricultural UniversityBeijing 100083China

Due to the widespread of adulteration of lipid in food and feed industry,the quality and safety of lipid are of public concern gradually.Firstly,the current article presents theory and mechanism of species identification of lipid by spectroscopic technique.Potential of near-infrared reflectance spectroscopy(Nir),Fourier transform infrared spectroscopy(ft-ir),and Fourier transform Raman spectroscopy(ft-Raman)applied to species identification of lipid were summarized.In addition,the relationship between lipid and spectroscopy as well as the recent advances of species identification of lipid were discussed.Research showed that ft-ir and ft-Raman spectroscopies possessed more efficient potential for species identification of lipid.Finally,prospects for future lipid detection and relative practical application,and combination of spectroscopy and other technique were further discussed.

关键词： feedstuff fatty acid Nir ft-ir ft-Raman spectroscopy