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Synthesis and characterization of Aryl Acylguanidines and Their Copper(Ⅱ) Complexes

Chinese Journal of Structural Chemistry 2019年第8期38卷 1283-1296页

作者： ZHOU Qi ZHANG Zhi-Jiao WANG Fan-Fan HAN Li ZHU Cheng-Ben LI Hai-Pu YANG Ying School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Water Environment and Agriculture product Safety Changsha 410083China

A series of eight N-mono-substituted aryl acylguanidines L1~8 were synthesized from the reactions of their parent acylthioureas and respective primary amines, including five R1C(O)N=C(NHR2)2 with balanced arms(denoted as R1–R2–R2: Ph–Ar’–Ar’, L1(1);Ph–Ar’’–Ar’’, L2(2);1-Naph–Ar’–Ar’, L3(3);1-Naph–Ar’’–Ar’’, L4(4);2-Naph–Ar’’–Ar’’, L[5(5);Ar’ = 2,6-Me2C6H3, Ar’’ = 2,6-iPr2C6H3) and three R1C(O)N=C(NHR2)NHR3 with unbalanced arms(denoted as R1–R2–R3: Ph–Ar’–Ph, L6(6);Ph–Ar’ –Ph, L7(7);Ph–Ar’ –Ar’, L8(8)). Treatment of L1~5(1~5) with copper acetate in a molar ratio of 2:1 in dichloromethane led to the formation of homoleptic Cu(Ⅱ) complexes trans-L2n’Cu(9~13), in which the Cu(Ⅱ) center was stabilized by deprotonated ligands Ln’(n = 1~5) in the O,N-bidentate mode. When similar reactions of L6(Ph–Ar’–Ph)(6) and L7(Ph–Ar’’–Ph)(7) that contain unbalanced arms were investigated, the Cu(Ⅱ) products trans-L26’Cu(14) and trans-L27’Cu(15) were formed by deprotonating the bulky amine groups in Ln(-NHAr’ for L6 and-NHAr’’ for L7) rather than the-NHPh group. In sharp contrast, trans-L28’Cu(16) was obtained from two-arm unbalanced L8(Ph–Ar’’–Ar’)(8) not by deprotonating the more bulky-NHAr’’ group but the relatively less bulky-NHAr’ group. In a further exploration, the reaction of 1:1 mixed ligands Ln and Lm with copper acetate was found to give only homoleptic Cu(Ⅱ) complex L2n’Cu instead of the heteroleptic one Ln’CuLm’. The in vitro antibacterial activity of Ln was evaluated against S. aureus, E. coli and C. albicans by determining the minimum inhibitory concentrations(MICs) using Kirby-Bauer test.

关键词： aryl acylguanidine Cu(Ⅱ) complex crystal structure ligand

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Unconventional Fluorescent and Multi-responsive Polyethyleneimine with LCST and UCST Behavior:Synthesis,characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第6期42卷 826-837页

作者： Feng-Ming Yin Li-Li Wu Shu-Sheng Li Xiao-Na Pan Xiao-Li Zhu Xu-Bao Jiang Xiang Zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Shandong Institute for product Quality Inspection Jinan250102China College of Chemical Engineering Tianjin UniversityTianjin300072China

Non-aromatic fluorescent and multi-responsive materials,exhibiting inherent fluorescence emission and controlled phase change,have garnered significant attention in recent ***,the underlying interaction between their fluorescent properties and phase transition remains *** this study,we synthesized a series of catalyst-free aza-Michael addition-based polyethyleneimine(RFPEI)materials by reacting polyethyleneimine(PEI)with N-isopropyl acrylamide(NIPAM).The resulting RFPEI was comprehensively characterized,and demonstrated dual-phase transition behavior(LCST and UCST)in water,which could be finely tuned by adjusting its composition or external factors such as ***,upon UV irradiation(365 nm),RFPEI exhibited strong fluorescence *** further investigated the effects of NIPAM grafting percentage to PEI,polymer concentration,and pH on the LCST/UCST and fluorescent properties of RFPEI aqueous ***,we showcased the great potential of RFPEI as a versatile tool for physiological cell imaging,trace detection,and controlled release of *** study presents a novel class of stimuli-responsive fluorescent materials with promising applications in the field of biomedicine.

关键词： Polyethyleneimine Multi-responsiveness Intrinsic fluorescence emission Cell imaging Controlled drug release

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Determination of Molecular Weight of FT synthetic wax by MALDI-TOF mass spectrometry

Determination of Molecular Weight of FT synthetic wax by MAL...

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2018年中国质谱学术大会（CMSC2018）

作者： Congyun Liu Qingqing Gai Linge Ma Yonglong Li Analytical and characterization Center National Institute of Clean-and-Low-Carbon Energy

FT Wax is an important coal chemical product which used in a wide range of applications, such as leather shoe oils, waxes products, daily necessities, paints and other aspects. It is mainly composed of straight chain alkanes, and has wider distillation range. It is a high-quality cracking raw material, which can obtain gas and diesel fractions by cracking, so the economic benefit of synthetic wax can be improved [1-2]. It is important to understand the composition in order to improve the added value of FT wax. This paper was aimed to determine the molecular weight of FT wax by MALDI-TOF mass spectrometry. The advantages of MALDI-TOF are: only one molecular ion is formed from each parent molecule, high sensitivity across a broad range of masses, ability to detect compounds of high molecular weight [3]. The wax sample was dissolved in heated CS2 and placed on the MALDI target, and 1μL of the matrix(DCTB) was then mixed in the wax solution. Then the target was introduced into the spectrometer. The spectra were recorded on an Autoflex Speed mass spectrometer from Bruker. The irradiation source was a pulsed nitrogen laser with a wavelength of 337 nm. Measurements were carried out using the following conditions: polarity-positive, flight pathlinear, 19 kV acceleration voltages. The pulsed ion extraction was 130 ns and the global attenuator offset was 30%. Figure 1 is the MALDI-TOF spectrum of FT-wax in the range 350-1200 *** to the results, the mass range was from 350 to1200 Da, the spectrum in the range of 350-550 Da presents a high intensity at m/z 451, 435, 468, the spectrum in the range of 550-850 Da presents a high intensity at m/z 675, 690, 704, this was assigned to a m/z 15 and m/z 16 fragment and indicated the presence of CH3. The spectrum in the range of 850-1200 Da presents a lower intensity. Compared with the results of simulated distillation and carbon distribution, the distillation range was 359-560℃, mainly composed with chain hydrocarbon of C23-C65

关键词： FT synthetic wax MALDI-TOF molecular weight

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Identification and characterization of Fischer-Tropsch oil by using GCxGC-TOF MS

Identification and characterization of Fischer-Tropsch oil b...

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2018年中国质谱学术大会（CMSC2018）

作者： Qingqing Gai Congyun Liu Linge Ma Yonglong Li Analytical and characterization Center National Institute of Clean-and-Low-Carbon Energy

Fischer-Tropsch(FT) synthesis is used as raw material to obtain hydrocarbons and other chemicals. The FT products are usually separated into wax, oil phase, water phase products and tail gas. The analysis of FT products is essential for product quality control, catalyst screening, kinetics study and engineering design. GC with MS or FID detection is the most common technique used to separate product compounds in FT synthesis [1]. It generally delivers good resolution, but separation problems with minor compounds may occur. The GCxGC has the advantage of increasing the resolution and sensitivity because of the re-concentration of the fraction through the modulation process. As the complexity of FT products requires analytical techniques with higher separation power [2], in this context, the benefits of GC×GC compared to one-dimensional GC(1 D-GC) for the investigation of the oil products of FT processes are *** FT oils are relatively simple and composed of mainly primary linear molecules present at percentage levels and very little secondary reaction products. However, a high degree of component co-elution is already observed in 1 DGC analysis(Fig.1). The co-elution is not necessarily the result of the limited peak capacity of the column but rather of a shared physical property. As shown in Fig.2, branched isomers of paraffins, olefins and oxygenates also elute in the same area of the GC chromatogram. GCxGC-TOFMS distinguishes these classes and identify each of the peaks in the chromatogram. Especially ketones, aldehydes, aromatics, ester and alcohols are identified, which are the lowlevel peaks co-eluted in the same region as branched isomers. GC×GC analyses provide valuable information of FT oil and allow the optimization of plant conditions to produce high-value fuels and chemicals.

关键词： Fischer-Tropsch oil comprehensive two-dimensional gas chromatography

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Identification and evolutionary characterization of SFBB genes in‘Yali’and its spontaneous self-compatible mutant‘Jinzhui’(Pyrus bretschneideri)

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Horticultural Plant Journal 2023年第5期9卷 909-919页

作者： Xu Huang Jiawei Mei Jing Zhang Xiao Liu Chunlei Wang School of Horticulture and Plant Protection International Research Laboratory of Agriculture and Agri-Product SafetyKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouJiangsu 225009China

Pears carry a gametophytic self-incompatibility(SI)*** this system,S-RNase is the SI pistil determinant,and S-locus F-box brothers(SFBBs)are candidate pollen ***,compared with apple,fewer SFBB genes were identified from pear,possibly caused by the lack of economic and effective ***,we used transcriptome sequencing on‘Yali’(Pyrus bretschneideri)to obtain sequence fragments of SFBB genes and then used polymerase chain reaction(PCR)to amplify the whole sequence of SFBB ***-seven SFBB genes,including22 full-length and five nonfull-length SFBB genes,were identified in‘Yali’(***).SFBBs linkage analysis by PCR-enzyme-linked immunoassay(ELISA)showed that 12 SFBB genes belong to the S21 locus,and 15 SFBB genes belong to the S34 *** analysis showed that SFBB genes from Pyrus were divided into 26 types,more than the original eight *** intrahaplotypic divergence of SFBBs is high and comparable to the allelic diversity of S-RNase,which is consistent with a nonself-recognition SI *** addition,the expression level of PbrSFBBs in‘Jinzhui’,the only known haploid pollen of a self-compatible mutant,was mostly approximately two times higher than in‘Yali’,which may be the reason for the self-compatible mutant.

关键词： Pyrus bretschneideri Self-incompatibility F-box protein Genotyping Transcriptome sequencing

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Determination of Moisture Sorption Isotherm Characteristics of Dehydrated Sorghum Flour （＂Ogi＂）

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Journal of Agricultural Science and Technology(B) 2013年第2期3卷 86-91页

作者： Ajiboye Solomon Oyerinde Visiting Scholar Biomass Characterization Laboratory Department of Biosystems Engineering Auburn University AuburnAlabama 36849 USA

Dehydrated sorghum flour （＂ogi＂） is useful as additional ingredient in certain food and pharmaceutical formulation, this could be obtained by soaking sorghum in water for 3 to 4 days, wet milling the soaked material, and fermentation for another 3 to 4 days. Typically, the fermented product is boiled into a pap or cooked into a stiff porridge. However, the fermented product can not be easily handled or stored and does not have a long shelf life （typically less than a week）. Dehydrating the fermented product into flour is one of the ways that is being employed to overcome these problems. Equilibrium moisture content （EMC） of dehydrated sorghum flour （aka ＂ogi＂） was therefore determined at two temperatures of 25℃ and 40℃ and four salt solutions. Zinc chloride （ZnCl2）, potassium acetate （KC2H3O2）, calcium chloride （CaCl2） and sodium chloride （NaCl） salts were prepared to correspond to equilibrium relative humidities of 10.0% to 75.4%. The moisture sorption characteristics of the sorghum product showed the characteristics S-shaped sorption isotherm curve that is typically obtained for agricultural products. The equilibrium data and the monomolccular layer moisture content values were estimated using the Brunauer-Emmett-Teller （BET） equation. The moisture content range for optimum storage of the dehydrated sorghum flour lies between 2.84% to 3.69% at 25℃ and 6.84% and 7.67% at 40℃. The information obtained from this study will help in the design and selection of storage and packaging systems for dehydrated sorghum flour.

关键词： Moisture adsorption sorghum flour equilibrium moisture content moisture isotherm storage stability

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Chemical characterization, release, and bioactivity of Eucalyptus camaldulensis polyphenols from freeze-dried sodium alginate and sodium carboxymethyl cellulose matrix

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Food Quality and Safety 2020年第4期4卷 203-212页

作者： Ozioma Forstinus Nwabor Sudarshan Singh Dwi Marlina Supayang Piyawan Voravuthikunchai Excellence Research Laboratory on Natural products Department of MicrobiologyFaculty of Science and Natural Product Research Center of ExcellencePrince of Songkla UniversityHat YaiSongkhlaThailand

Crude ethanolic extract of Eucalyptus camaldulensis was encapsulated with sodium alginate- sodium carboxymethyl cellulose (CMC) using freeze-drying techniques. The microcapsules were characterized for particle size, morphology, physicochemical parameters, and micromeritics properties. Antioxidant and antimicrobial activities of the microcapsules were also demonstrated. Results revealed an irregular-shaped microparticles with a mean diameter ranging from 6.7 to 26.6 μm. Zeta potential and polydispersity index ranged from −17.01 to 2.23 mV and 0.34 to 0.49, respectively. Percentage yield ranged between 70.4 and 81.5 per cent whereas encapsulation efficiency ranged between 74.2 ± 0.011 and 82.43 ± 0.77 per cent. Swelling index and solubility varied inversely with extract concentration, with a range of 54.4%-84.0% and 18.8%-22.2%, respectively. Antioxidant activities varied directly with the concentration of the extract. Minimum inhibitory and minimum bactericidal concentrations of the microcapsules against Gram-positive foodborne pathogens ranged from 0.19 to 3.12 and 0.19-12.25 mg/ml, respectively. The Higuchi model indicated a time-dependent, delayed, and regulated release of polyphenols at 37°C. The results suggested that alginate-CMC possessed good encapsulant properties that preserved the bioactive extract, thus might be employed for application of natural products in food systems.

关键词： microencapsulation freeze-drying antimicrobial antioxidant Eucalyptus camaldulensis regulated release

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Interfacial characterization of resistance spot welded joint of steel and aluminum alloy

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China Welding 2010年第4期19卷 6-10页

作者：张伟华孙大千殷世强韩立军邱小明陈庆雷 School of Materials Science and Engineering Jilin University Changehun 130022 Department of product Management FAW-Volkswagen Automobile Co. Ltd. Changchun130011

The dissimilar material resistance spot welding of galvanized high strength steel and aluminum alloy had been conducted. The welded joint exhibited a thin reaction layer composed of Fe2Al5 and Fe4Al13 phases at steel/aluminum interface. The welded joint presented a tensile shear load of 3.3 kN with an aluminum alloy nugget diameter of 5.7 mm. The interfacial failure mode was observed for the tensile shear specimen and fracture occurred at reaction layer and aluminum alloy fusion zone beside the interface. The reaction layer with compounds was the main reason for reduction of the welded joint mechanical property.

关键词： high strength steel aluminum alloy resistance spot welded joint interfacial characterization

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characterization of Perfluorooctane Sulfonate by Gas Chromatography/Mass Spectrometry

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Journal of Donghua University(English Edition) 2010年第6期27卷 819-824页

作者：孟丽娟杨勇林苗 Key Laboratory of Science & Technology of Eco-Textile Ministry of EducationDonghua University Inspection Center of Industrial product & Raw-Materials Shanghai Entry-Exit Inspection & Quarantine Bureau

With quantitative conversion to volatile derivatives,substance such as perfluorooctane sulfonate(PFOS)that is difficult to analyze can be separated by conventional techniques and then be *** this paper,the methods and procedures in which perfluorooctane sulfonic acids were converted to corresponding sulfonic ester by reaction with triethylorthoacetate(TEOA)in the presence of solvent were described,and then PFOS was analyzed as ethyl ester *** spectra(MS)were generated using electron ionization(EI)*** the EI spectra of the volatile derivatives show ions characteristic of both the fluorinated hydrocarbon and the sulfonic ester portion of the molecules.

关键词： perfluorooctane sulfonate(PFOS) GC/EI-MS characterization derivation

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Synthesis, characterization and Gas Sensing Properties of In(OH)_3 and In_2O_3 Nanorods through Carbon Spheres Template Method

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Journal of Materials Science & Technology 2012年第5期28卷 396-400页

作者： Xifeng Lu Lei Zhang Hui Zhao Kai Yan Yan Cao Lumin Meng Lunan Institute of Coal Chemical Engineering Jining 272000China College of Chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004China Jining Institute of Supervision and Inspection on product Quality Jining 272000China

Poly-crystalline In（OH） 3 nanorods have been successfully prepared via a urea-based precipitation using the colloidal carbon spheres as the templates. After calcinations, the resulted In 2 O 3 nanorods with poly-crystalline structure were fabricated. Structure and morphology of the product were characterized by X-ray diffraction （XRD）, and transmission electron microscopy （TEM）. The possible formation process was schemed. The sensor gas properties towards C 2 H 5 OH and CO were examined.

关键词： Nanostructures Self-assembly characterization Gas sensor

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