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Petrogenesis and Metallogenic Implications of A-type Granites in the Mid-Late Jurassic Dayishan Complex,Southern Hunan Province,South China 被引量:2
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作者 ZHANG Meng JIANG Yaohui +1 位作者 LIU Yunchao HAN Boning 《Acta Geologica Sinica(English Edition)》 2025年第1期100-113,共14页
The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and... The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and whole-rock geochemistry for this complex.Our findings indicate that the southern complex consists of(amphibole-bearing)biotite granites and muscovite granites emplaced at 153-151 Ma,and the central and northern complex consists of two-mica granites and tourmaline-bearing muscovite granites,respectively with the former emplaced at 164 Ma and the latter at 150 Ma.The(amphibole-bearing)biotite granites have SiO_(2) contents of 68.0-73.8 wt% and are enriched in alkalis and rare earth elements and depleted in Sr and Ba.They display Zr+Y+Ce+Nb>350 ppm and 10000×Ga/Al>2.6 along with high zircon saturation temperatures(821-883oC).The two-mica granites and(tourmaline-bearing)muscovite granites have high SiO_(2)(74.4-77.3 wt%)and low Ga/Al,Zr+Nb+Ce+Y,K/Rb,Zr/Hf,and Nb/Ta along with low zircon saturation temperatures(709-817℃).Geochemical characteristics suggest that the(amphibole-bearing)biotite granites are A-type granites generated through shallow dehydration melting of early Paleozoic granitoids,and that the two-mica granites and(tourmaline-bearing)muscovite granites are fractionated A-type granites produced through fractionation crystallization from the(amphibole-bearing)biotite granites accompanied by fluid fractionation. 展开更多
关键词 a-type granite shallow dehydration melting FRACTIONATION South China
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 starch particle Physicochemical properties starch function Resistant starch starch extraction
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Geochemistry and U-Th-Pb Geochronology of Monazite in the Suzhou A-type Granite Pluton:Implications for Nb-Ta Mineralization
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作者 PAN Wei HU Qinghai +7 位作者 WU Hui BAN Yiyi ZHANG Bimin SUN Binbin WANG Wei LIU Xuemin WANG Xueqiu GONG Qiuli 《Acta Geologica Sinica(English Edition)》 2025年第4期1025-1041,共17页
The Suzhou granitic pluton is the first identified Nb-Ta-rich granite in China.To reveal the genetic link between the sequence of magmatic and hydrothermal evolution and Nb-Ta mineralization in different intrusive pha... The Suzhou granitic pluton is the first identified Nb-Ta-rich granite in China.To reveal the genetic link between the sequence of magmatic and hydrothermal evolution and Nb-Ta mineralization in different intrusive phases of the Suzhou granite,whole-rock geochemistry,geochemistry and U-Th-Pb dating of monazite was analyzed.The unique geochemical characteristics show that the Suzhou pluton can be discriminated as an A-type granite.LA-ICP-MS U-Th-Pb dating of monazite in both the medium-and coarse-grained biotite granite(MBG)and the fine-grained biotite granite(FBG)indicates that the granite formed between 124 and 127 Ma.Based on geochemical characteristics and mineral textures,the MBG(Mnz-Ia)and FBG(Mnz-Ib)monazites are classified as magmatic monazites;another monazite(Mnz-II)from the MBG formed during a magmatic-hydrothermal transitional stage.Nb-Ta in the Suzhou pluton gradually concentrated during fractional crystallization and alteration of Ti-rich minerals and biotite.Ultimately,with the involvement of F-Li-rich fluid,Nb-Ta mineralization occurred during the magmatic-hydrothermal transition.The Suzhou pluton is considered part of a 600-km-and NE-SW-trending Nb-rich A-type granite belt together with other Early Cretaceous A-type granites in the Jiangnan Orogen that offers prospects of a new target for Nb-Ta prospecting. 展开更多
关键词 GEOCHRONOLOGY a-type granite MONAZITE Nb-Ta mineralization Suzhou pluton
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Petrogenesis of the Dupangling Granitic Complex,South China:Implications for A-type and Strongly Peraluminous Granite Origin
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作者 JIANG Yaohui ZHAO Yajie +1 位作者 LIU Yunchao HAN Boning 《Acta Geologica Sinica(English Edition)》 2025年第3期725-742,共18页
Granite origin is crucial to understanding the evolution of continental crust,yet many concerns about granite genesis remain yielding ongoing debates.A new integrated study of petrology,geochronology,mineral chemistry... Granite origin is crucial to understanding the evolution of continental crust,yet many concerns about granite genesis remain yielding ongoing debates.A new integrated study of petrology,geochronology,mineral chemistry and whole-rock geochemistry of the Dupangling granitic complex in South China,indicate that the granites in the western complex were emplaced during the Caledonian(418 Ma);they have SiO_(2)contents of 68.1-70.4 wt%,and are calc-alkaline and strongly peraluminous with high maficity[(TFe_(2)O_(3)+MgO)>4.0 wt%]and exhibit^(87)Sr/^(86)Sr(t)of 0.7234-0.7311 andε_(Nd)(t)of-9.0 to-6.7.The granites in the eastern complex,emplaced during the Indosinian(212 Ma),have high SiO_(2)contents(73.3-79.8 wt%)and exhibit affinities with A-type granites,such as enrichment in alkalis and rare earth elements(REEs),and depletion in Sr and Ba along with high TFeO/(TFeO+MgO),Ga/Al and Zr+Y+Ce+Nb;these granites exhibit^(87)Sr/^(86)Sr(t)of 0.7221 andε_(Nd)(t)of-9.2 to-7.5.Geochemical characteristics suggest that the older Caledonian granites were derived through dehydration melting of Paleoproterozoic metasedimentary rocks plus additional(~20%-32%)input from mafic magma,whereas the Indosinian granites were generated through shallow dehydration melting of the Caledonian granitoids. 展开更多
关键词 peraluminous granite a-type granite MAGMATISM CALEDONIAN INDOSINIAN South China
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Aqueous Ionic Liquid Mediated Hydrolysis of Native Corn Starch to Obtain Different Low Molecular Weight Starch
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作者 YANG Rui WANG Xiaolin +1 位作者 DANG Qian LIU Zhengping 《高等学校化学学报》 北大核心 2026年第1期153-161,共9页
In this work,we proposed a strategy for the hydrolysis of native corn starch after the treatment of corn starch in an ionic liquid aqueous solution,and it is an awfully“green”and simple means to obtain starch with l... In this work,we proposed a strategy for the hydrolysis of native corn starch after the treatment of corn starch in an ionic liquid aqueous solution,and it is an awfully“green”and simple means to obtain starch with low molecular weight and amorphous state.X-ray diffraction results revealed that the natural starch crystalline region was largely disrupted by ionic liquid owing to the broken intermolecular and intramolecular hydrogen bonds.After hydrolysis,the morphology of starch changed from particles of native corn starch into little pieces,and their molecular weight could be effectively regulated during the hydrolysis process,and also the hydrolyzed starch samples exhibited decreased thermal stability with the extension of hydrolysis time.This work would counsel as a powerful tool for the development of native starch in realistic applications. 展开更多
关键词 Native corn starch Ionic liquid HYDROLYSIS Molecular weight
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Bio-Based Foams from Agricultural Waste:Optimizing Corn Starch-Corn Husk Composites with Xanthan Gum for Cushioning Applications
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作者 Manisara Phiriyawirut Kanbhanu Wachararuangroong +1 位作者 Manisara Wongsaroj Napat Arompijit 《Journal of Renewable Materials》 2026年第3期148-164,共17页
With the escalating environmental impact of petrochemical-based packaging,the development of biodegradable alternatives from agricultural waste has become imperative.This study describes the fabrication and optimizati... With the escalating environmental impact of petrochemical-based packaging,the development of biodegradable alternatives from agricultural waste has become imperative.This study describes the fabrication and optimization of a sustainable,bio-based cushioning material derived from a corn starch foam matrix and corn husk fibers via compression molding.The investigation of starch ratios revealed that 100%normal corn starch(NCS)provided superior expansion and structural integrity compared to waxy starch,which exhibited significant cell wall collapse under SEM analysis.To enhance formability,xanthan gum(XG)was incorporated as a stabilizer;a 1.0%(w/w)concentration was found to be the morphological inflection point,yielding a refined closed-cell structure and a bulk density of 0.43 g/cm^(3).The stabilized matrix was reinforced with 2.0%to 6.0%(w/w)corn husk fibers pre-treated with tetraethoxy silane(TEOS)to improve interfacial adhesion.The addition of 6.0%fibers significantly augmented the material’s energy absorption capacity,achieving a peak impact strength of 1.87±0.50 kJ/m^(2)and a compressive strength of 0.56 N/mm^(2).These results demonstrate that the optimized agricultural waste-derived composite effectively surpasses the load-bearing capabilities of traditional commercial foams,offering a viable,eco-friendly solution for high-load protective packaging. 展开更多
关键词 starch foam corn starch corn husk fiber xanthan gum waxy corn starch
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Presence of Acetogenins in Starches and Pectins Extracted from Soursop(Annona muricata L.)Fruits
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作者 Miguelángel De los Santos-Santos Rosendo Balois-Morales +6 位作者 Juan Esteban Bello-Lara JoséOrlando Jiménez-Zurita Graciela Guadalupe López-Guzmán Efigenia Montalvo-González Guillermo Berumen-Varela Carlos Azhael Rodríguez-Guzmán Andrés Eloy León-Fernández 《Phyton-International Journal of Experimental Botany》 2026年第2期139-154,共16页
Acetogenins are lipidic polyketides with antioxidant,antimicrobial,cytotoxic,and antitumor properties,mainly found in the roots,stems,bark,leaves,and fruits(particularly the seeds)of Annonaceae species.Previous studie... Acetogenins are lipidic polyketides with antioxidant,antimicrobial,cytotoxic,and antitumor properties,mainly found in the roots,stems,bark,leaves,and fruits(particularly the seeds)of Annonaceae species.Previous studies have identified acetogenins in the peel and pulp of soursop(Annona muricata L.)fruits.In this research,acetogenins present in starch and pectin extracted from these fruits were analyzed and identified,given their potential importance in the pharmaceutical and possibly in the food industries.The objective was to identify and quantify acetogenins in starch and pectin of soursop fruits.Extraction of both polysaccharides was performed using conventional and ultrasound-assisted methods,obtaining two types of pastes(white and brown).These were characterized by Fourier Transform Infrared Spectroscopy(FTIR).Methanolic extracts from the pastes were analyzed by thin-layer chromatography and open-column fractionation.Acetogenins were identified and quantified by high-performance liquid chromatography(HPLC).The compounds identified were pseudoannonacin and anonacin.In pectin,the concentration(μg g^(−1)of dry basis P/A)of pseudoannonacin was 340.06(conventional)and 452.80(ultrasound-assisted),while for anonacin it was 302.29(conventional)and 397.23(ultrasound-assisted).In starch,the concentration(μg g^(−1)of dry basis P/A)of pseudoannonacin was 20.72(conventional)and 21.60(ultrasound-assisted),whereas anonacin showed concentrations of 1.63(conventional)and 3.12(ultrasound-assisted).These results confirm the presence of anonacin and pseudoannonacin in both starch and pectin of soursop fruits,with pseudoannonacin being the most abundant acetogenin detected. 展开更多
关键词 ACETOGENINS anonacin PECTIN pseudoannonacin starch
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Plywood Bio-Adhesives by Oxidized Lignin Urea Bridged with Oxidized Starch
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作者 Hamed Younesi-Kordkheili Antonio Pizzi 《Journal of Renewable Materials》 2026年第1期1-15,共15页
The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different cont... The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different contents(20%,30%,and 40%)were used to prepare the starch-urea-lignin(SUL)and starch-urea-oxidized lignin(SUOL)resin.Sodium persulfate(SPS)as oxidizer was employed to oxidize both starch and lignin.Urea was just used as a low cost and effective crosslinker in the resin composition.The properties of the synthesized resins and the plywood panels bonded with themweremeasured according to relevant standards.The viscosity and gel time of the SUOL resins containing oxidized lignin are respectively higher and faster than for non-modified lignin(SUL).The lignin phenolic hydroxyl groups(-OH)proportion was markedly increased by oxidation as shown by Fourier Transform Infrared(FTIR)spectrometry.The molecular mass and the polydispersity of the lignin did also decrease by its oxidization pretreatment.DSC analysis showed a decrease of the glass transition temperature of the lignin(Tg)due to its oxidation.The thermal analysis of the oxidized lignin SUOL resin also showed that it had a lower peak temperature than the SUL equivalent non-modified lignin resin.The plywood panels bonded with oxidized lignin gave acceptable bending modulus,bending strength,peak temperature by thermal analysis and dry shear strength as well as a better plywood dimensional stability when used in the SUOL formulation.The synthesized SUOL adhesive is a lignin-derived,totally bio,no-aldehyde added,inexpensive resin applicable to bond plywood. 展开更多
关键词 Oxidized starch oxidized lignin UREA oxidation PLYWOOD sodium persulfate bio-adhesive WOOD
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Tailoring pretreatment-mediated microcrystalline structure of starch-based hard carbon for high-performance sodiumion batteries
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作者 Shaojie Qin Zhenyuan Xie +5 位作者 Xianrui Wu Yanbing Cheng Yiyong Zhang Ziyi Zhu Shuang Zhou Xue Li 《Materials Futures》 2026年第2期77-91,共15页
The principal challenge in optimizing biomass-derived hard carbon(HC)is the concurrent enhancement of specific capacity,cycling durability,and rate performance,as these properties are closely related to the disordered... The principal challenge in optimizing biomass-derived hard carbon(HC)is the concurrent enhancement of specific capacity,cycling durability,and rate performance,as these properties are closely related to the disordered carbon network and abundant pore structure.However,inadequate controllability of morphology,insufficiently regulated pore structures,and the complexity of post-processing modifications hinders the practical application of HC.In this work,a high-temperature and high-pressure expansion pretreatment technique is proposed to regulate the structure of starch precursors,enabling the precise design of ordered graphitic-like microcrystals and closed pores within HC.The optimized starch-based HC displayed remarkable electrochemical efficiency,with a reversible capacity of 332.0 mAh g^(-1),an initial Coulombic efficiency of 90.4%,and stable cycling over 3000 cycles.Meanwhile,advanced full-cell utilizing Na4Fe3(PO_(4))_(2)P_(2)O_(7) cathode achieve stable cycling performance exceeding 1000 cycles,demonstrating outstanding performance.This research innovatively employs a green expansion process to achieve structural regulation of HC,thereby providing an environmentally friendly and economically viable technical pathway for its large-scale production. 展开更多
关键词 sodium-ion batteries biomass hard carbon anode starch expansion technology
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Effects of changing assimilate supply on starch synthesis in maize kernels under high temperature stress
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作者 Teng Li Shumei Wang +5 位作者 Qing Liu Xuepeng Zhang Lin Chen Yuanquan Chen Wangsheng Gao Peng Sui 《Journal of Integrative Agriculture》 2026年第2期639-647,共9页
High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assim... High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assimilate supply or direct inhibition on kernel metabolism.To clarify these mechanisms,a heat-sensitive maize hybrid,Xianyu 335 (XY),was exposed to 30℃/20℃ (maximum/minimum temperature,control) and 40℃/30℃ for seven consecutive days during the seed setting stage.Synchronous pollination (SP),apical pollination (AP),and shading treatments were applied to manipulate the inherent source–sink ratio in maize plants.Results showed that apical kernel weight decreased by 11.9%under 40℃ in the SP treatment.The ^(13)C content,starch accumulation,and cell-wall invertase (CWIN) activity also declined by 15.9,36.7,and 16.4%,respectively,under HT.In the shading treatment,40℃/30℃ caused even greater reductions in^(13)C content,starch accumulation,and CWIN activity due to diminished assimilate supply.Conversely,in the AP treatment,starch content and CWIN activity increased by 22.0 and 18.5%,respectively,under 40℃/30℃,resulting in kernel weight and ^(13)C content similar to those in SP and shading treatments regardless of temperature.Consistent with apical kernels under AP,HT did not negatively affect middle kernels in either SP or shading treatments,as kernel weight and starch content remained unchanged under HT.Although all kernels were exposed to the same HT or control environment,their responses varied a lot.The impaired starch synthesis in apical kernels under HT was rescued by increasing carbon supply via AP treatment.The contrasting performance among middle kernels,apical kernels under AP,and apical kernels under SP or shading indicates that reduced carbon supply is a critical factor underlying inhibited starch accumulation.Our findings provide a theoretical basis for further understanding kernel abortion under HT. 展开更多
关键词 high temperature stress MAIZE seed setting stage cell wall invertase starch synthesis
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Sustainable Biopolymer Packaging Utilizing Non-Food-Competing Starches Derived from Rubber Cassava and Banana Wastes
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作者 Fitra Yurid Nadiatus Silmi +3 位作者 Heni Rachmawati Nanda Nagara Riyanti Ekafitri Athanasia Amanda Septevani 《Journal of Renewable Materials》 2026年第2期84-105,共22页
This study investigates the potential of starch extracted from underutilized agro-industrial resources as non-food-competing raw materials for the development of flexible bioplastics for food packaging applications.St... This study investigates the potential of starch extracted from underutilized agro-industrial resources as non-food-competing raw materials for the development of flexible bioplastics for food packaging applications.Starch was extracted from three biomass sources:rubber cassava(Manihot glaziovii),banana stem,and banana peel from Ambonese banana(Musa acuminata L.).Rubber cassava starch(SRC)exhibited the highest starch yield(50.68±0.28%),significantly surpassing banana stem(SBS,14.20±0.25%)and banana peel(SBP,3.07±0.15%).The amylose contents of SRC,SBS,and SBP were 28.18%,52.80%,and 56.57%,respectively,while their amylopectin contents were 71.83%,47.20%,and 43.43%.FTIR spectra confirmed the absence of cyanogenic groups in SRC,indicating its safety for packaging applications.XRD analysis revealed that PSRC films were predominantly amorphous,while PSBS and PSBP showed higher crystallinity.The enhancement of mechanical properties,specifically PSBS,showed the highest tensile strength at 16.04±0.56 MPa,whereas PSRC demonstrated the highest elongation at break at 23.57±0.40%,which could be attributed to the inherent characteristics of the starch sources.Additionally,PSRC film exhibited the highest transparency at 60.2%,the greatest water solubility at 34.92%,and the lowest water contact angle at 41.58○,confirming its more hydrophilic nature compared to other films.This work highlights the potential of low-cost,sustainable,and non-food agro-industrial starch sources as promising candidates for the development of flexible,eco-friendly bioplastics. 展开更多
关键词 Rubber cassava ambonese banana agro-industrial resources bioplastic film banana stem banana peel starch
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Enhancing Corn Starch-Poly(Vinyl Alcohol)and Glycerol Composite Films with Citric Acid Cross-Linking Mechanism:A Green Approach to High-Performance Packaging Materials
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作者 Herlina Marta Novita Indrianti +6 位作者 Allifiyah Josi Nur Aziza Enny Sholichah Titik Budiati Achmat Sarifudin Yana Cahyana Nandi Sukri Aldila Din Pangawikan 《Journal of Renewable Materials》 2026年第1期127-147,共21页
Corn starch(CS)is a renewable,biodegradable polysaccharide valued for its film-forming ability,yet native CS films exhibit lowmechanical strength,highwater sensitivity,and limited thermal stability.This study improves... Corn starch(CS)is a renewable,biodegradable polysaccharide valued for its film-forming ability,yet native CS films exhibit lowmechanical strength,highwater sensitivity,and limited thermal stability.This study improves CS-based films by blending with poly(vinyl alcohol)(PVA)or glycerol(GLY)and using citric acid(CA)as a green,non-toxic cross-linker.Composite films were prepared by casting CS–PVA or CS-GLY with CA at 0%-0.20%(w/w of starch).The influence of CA on physicochemical,mechanical,optical,thermal,and water barrier properties was evaluated.CA crosslinking markedly enhanced the tensile strength,water resistance,and thermal stability of CS-PVA films while increasing transparency in CS–GLY films.At 0.20%CA,the composite achieved 34.99MPa tensile strength,reducedwater vapor permeability,andminimized water uptake.FTIR confirmed ester bond formation between CAand hydroxyl groups of CS,PVA,and GLY,whereas thermal analysis showed higher decomposition temperatures and lower weight loss in crosslinked films.Increasing CA levels also decreased opacity and improved light transmittance,indicating greater homogeneity and reduced crystallinity.This dual-polymer matrix combined with a natural crosslinking strategy provides a sustainable route to high-performance,biodegradable CS-based packaging materials. 展开更多
关键词 Corn starch poly(vinyl alcohol) GLYCEROL citric acid cross-linking renewable packaging materials biopolymer films
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Expression,Purification and Activity Detection of VP1 of A-type FMDV 被引量:4
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作者 李菁 林彤 +4 位作者 高闪电 丛国正 独军政 邵军军 常惠芸 《Agricultural Science & Technology》 CAS 2010年第2期23-26,共4页
[Objective] The research aimed to induce the expression of FMDV structural protein VP1 in E.coli and purify the protein,then detect the activity.[Method] The fragment coding VP1 was amplified by PCR and doubly digeste... [Objective] The research aimed to induce the expression of FMDV structural protein VP1 in E.coli and purify the protein,then detect the activity.[Method] The fragment coding VP1 was amplified by PCR and doubly digested with BamH Ⅰ and XhoⅠ,then cloned into expression vector pGEX-4T-1 and pPROExHTb respectively to get recombinant plasmid pGEX-4T-1-VP1 and pPROExHTb-VP1.The recombinant plasmid pGEX-4T-1-VP1 and pPROExHTb-VP1 was transformed into E.coli BL21(DE3)and induced by IPTG,fusion protein was identifie... 展开更多
关键词 a-type FMDV Structural protein VP1 Expression and purification
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Influence of A-type Zeolite on Methane Hydrate Formation 被引量:9
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作者 臧小亚 杜建伟 +2 位作者 梁德青 樊栓狮 唐翠萍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期854-859,共6页
The porous medium has an important effect on hydrate formation.In this paper,the formation process and the gas storage capacity of the methane hydrate were investigated with A-type zeolite and Sodium Dodecyl Sulfate (... The porous medium has an important effect on hydrate formation.In this paper,the formation process and the gas storage capacity of the methane hydrate were investigated with A-type zeolite and Sodium Dodecyl Sulfate (SDS) existing in the system.The results show that A-type zeolite can influence methane hydrate formation.At the temperature of 273.5 K and pressure of 8.3 MPa,the distilled water with A-type zeolite can form methane hydrate with gaseous methane in 12 hours.The formation process of the system with A-type zeolite was quite steady and the amount of A-type zeolite can influence the gas storage capacity significantly.The adding of A-type zeolite with 0.067 g·(g water)-1 into 2×10-3 g·g-1 SDS-water solution can increase the gas storage capacity,and the maximum increase rate was 31%.Simultaneously the promotion effect on hydrate formation of 3A-type zeolite is much more obvious than that of 5A-type zeolite when the water adding amounts are 0.033 g·g-1 and 0.067 g·g-1 at the experimental conditions. 展开更多
关键词 HYDRATE FORMATION gas storage a-type zeolite
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Geochronological and Geochemical Constrains on Petrogenesis of the Jietebutiao A-type Granite in West Junggar,Xinjiang 被引量:4
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作者 YANG Gaoxue LI Yongjun +3 位作者 TONG Lili ZHANG Bing TIAN Zhixian YANG Baokai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第1期131-147,共17页
Late Paleozoic post-collisional granitoids are widespread in West Junggar, as well as northern Xinjiang. As a representative of those intrusions, the Jietebutiao granite occurs in the southwestern margin of the West J... Late Paleozoic post-collisional granitoids are widespread in West Junggar, as well as northern Xinjiang. As a representative of those intrusions, the Jietebutiao granite occurs in the southwestern margin of the West Junggar (northwest China), and is mainly composed of mid-coarse- grained monzogranite and syenogranite. In the present study, we report the results of high-precision zircon laser-ablation-inductively-coupled plasma mass-spectrometry U-Pb dating on the Jietebutiao granite for the first time, and yield weighted mean 2~~pb/23SU ages of 287 + 9 Ma and 278 ~ 3 Ma for monzogranite and syenogranite, respectively. The Jietebutiao granite has a pronounced A-type affinity; it is metaluminous to slightly peraluminous; has a high-K calc-alkaline composition; high concentrations of Na20 + I(20, varying from 6.8 to 8.5 wt%; high FeOt/MgO; 10 000Ga/AI ratios, a low CaO, MgO, and TiO2 content; enriched in some large ion lithophile elements (LILE, such as Rb and Th) and high field strength elements (HFSE, such as Zr, Hf, and Y); and depleted in Sr, Ba, and Ti. In addition, the granite has a relatively high rare earth element (REE) content (except for Eu), with significant negative Eu anomalies (Eu/Eu* = 0.01-0.72), and showing slight tetrad REE patterns and non-charge and radius controlled (CHARAC) trace element behavior. Petrographic, geochemical, and geochronological data suggest that the parental magma of Jietebutiao intrusions are of mixed origin, and are most probably formed by the interaction between the lower crust- and mantle-derived magmas in the Early Permian post-collisional tectonic setting. The basaltic magmas underplated and interacted with the lower crust that was dominated by deeply buried arc (and back-arc basin) series and the oceanic crust formed in the Paleozoic, and then triggered the partial melting of the juvenile lower crust, producing voluminous granitic melts and forming the Jietebutiao A2-type monzogranites, with the lithospheric mantle progressively thinning and rifting to form Al-type granites, such as syenogranites, in the Jietebutiao pluton. This further proves the important contribution of Late Paleozoic granitic magmatism in terms of vertical crustal growth in northern Xinjiang. 展开更多
关键词 a-type granite GEOCHRONOLOGY PETROGENESIS POST-COLLISIONAL West Junggar
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Petrogenesis and Tectonic Implications of Peralkaline A-Type Granites and Syenites from the Suizhou-Zaoyang Region,Central China 被引量:8
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作者 Hafizullah Abba Ahmed Changqian Ma +4 位作者 Lianxun Wang Ladislav A.Palinkas Musa Bala Girei Yuxiang Zhu Mukhtar Habib 《Journal of Earth Science》 SCIE CAS CSCD 2018年第5期1181-1202,共22页
In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A... In this study, we present systematic petrological, geochemical, LA-ICP-MS zircon U-Pb ages and Nd isotopic data for the A-type granites and syenites from Suizhou-Zaoyang region. The results show that the peralkaline A-type granites and syenites were episodically emplaced in Suizhou-Zaoyang region between 450±3 and 441±7 Ma which corresponds to Late Ordovician and Early Silurian periods, respectively. Petrologically, the syenite-peralkaline granite association comprises of nephefine normative-syenite and alkaline granite in Guanzishan and quartz normative syenite and alkafine granite in Huangyangshan. The syenite-granite associations are ferroan to alkali in composition. They depict characteristics of typical OIB (oceanic island basalts) derived A-type granites in multi-elements primitive normalized diagram and Ybffa vs. Y/Nb as well as Ce/Nb vs. Y/Nb binary plots. Significant depletion in Ba, Sr, P, Ti and Eu indicates fractionation of feldspars, biotite, amphiboles and Ti-rich augite. The values of eNd(t) in Guanzishan nepheline syenite and alkaline granite are +1.81 and +2.26, respectively and the calculated two-stage model age for these rocks are 1 040 and 1 003 Ma, respectively. On the other hand, the Huangyangshan alkaline granite has eNd(t) values ranging from +2.61 to +3.46 and a relatively younger two-stage Nd model age values ranging from 906 to 975 Ma, respectively. Based on these data, we inferred that the Guanzishan nepheline syenites and granites were formed from fractional crystallization of OIB-like basic magmas derived from upweliing of metasomatized lithospheric mantle. The Huangyangshan quartz syenite and granite on the other hand, were formed from similar magmas through fractional crystallization with low input from the ancient crustal rocks. Typically, the rocks exhibit Al-type granite affinity and classified as within plate granites associated with the Ordovician crustal extension and the Silurian rifting. 展开更多
关键词 Huangyangshan Guanzishan OIB derived a-type granites nepheline syenite alkaline granite South Qinling Suizhou-Zaoyang region.
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Geochronology and Geochemistry of the Xingxingxia Triassic A-type Granites in Central Tianshan,NW China:Petrogenesis and Tectonic Implications 被引量:6
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作者 HUANG Zengbao LI Xiyao +1 位作者 ZHAO Hao LU Qing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期337-351,共15页
The Triassic granitoids in Central Tianshan play a key role in determining the petrogenesis and tectonic evolution on the southern margin of the Central Asian orogenic belt.In this study,we present SHRIMP zircon U-Pb ... The Triassic granitoids in Central Tianshan play a key role in determining the petrogenesis and tectonic evolution on the southern margin of the Central Asian orogenic belt.In this study,we present SHRIMP zircon U-Pb ages,Hf isotopic and geochemical data on the Xingxingxia biotite granite,amazonite granite and granitic pegmatite in Central Tianshan,NW China.Zircon U-Pb dating yielded formation ages of 242 Ma for the biotite granite and 240 Ma for the amazonite granite.These granitoid rocks have high K_(2)O with low MgO and CaO contents.They are enriched in Nb,Ta,Hf and Y,while being depleted in Ba and Sr,showing flat HREE patterns and negative Eu anomalies.They have typical A-type granite geochemical signatures with high Ga/A_(1)(8–13)and TFeO/(TFeO+MgO)ratios,showing an A_(2) affinity for biotite granite and an A_(1) affinity for amazonite granite and granitic pegmatite.Zircon ε_(Hf)(t)values of the granitoids are 0.45–2.66,with Hf model ages of 0.99–1.17 Ga.This suggests that these A-type granites originated from partial melting of the lower crust.We propose that Xingxingxia Triassic A-type granites formed under lithospheric extension from post-orogenic to anorogenic intraplate settings and NE-trending regional strike-slip fault-controlled magma emplacement in the upper crust. 展开更多
关键词 TRIASSIC a-type granite Xingxingxia Central Tianshan Central Asian orogenic belt
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Age and geochemistry of Early Ordovician A-type granites in the Northeastern Songnen Block,NE China 被引量:3
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作者 Changzhou Deng Deyou Sun +4 位作者 Guangyi Sun Changlu Lv Zhen Qin Xianquan Ping Guanghui Li 《Acta Geochimica》 EI CAS CSCD 2018年第6期805-819,共15页
Early Ordovician A-type granites in the northeastern(NE) Songnen Block NE China were studied to better understand the geodynamic settings in this region.This research presents new zircon U–Pb ages and wholerock geoch... Early Ordovician A-type granites in the northeastern(NE) Songnen Block NE China were studied to better understand the geodynamic settings in this region.This research presents new zircon U–Pb ages and wholerock geochemical data for the Early Ordovician granites in the NE Songnen Block. Zircon U–Pb dating indicates that the granite in the Cuibei, Hongxing, and Meixi areas in the NE Songnen Block formed in the Early Ordovician with ages of 471–479 Ma. The granites show geochemical characteristics of high SiO2 and K2 O compositions and low FeOT, MgO, CaO, and P2 O5 compositions. They belong to a high K calc-alkaline series and display a weak peraluminous featurPe with A/CNK values of 0.98–1.14. The rocks have aREE composition of 249.98–423.94 ppm,and are enriched in LREE with(La/Yb)Nvalues of2.87–9.87, and display obvious Eu anomalies(d Eu =0.01–0.29). Trace elements of the studied granites are characterized by enrichment in Rb, Th, U, Pb, Hf, and Sm,and depletion of Ba, Nb, Ta, and Sr. They display geochemical features of high Zr +Y + Nb+Ce values(324–795 ppm) and Ga/Al ratios consistent with A-type granites. Based on particular geochemical features, such as high Rb/Nb(7.98–24.19) and Y/Nb(1.07–3.43), the studied A-type granites can be further classified as an A2-type subgroup. This research indicates that the Early Ordovician A-type granites were formed by the partial melting of ancient crust in an extensional setting. Lower Sr/Y and(Ho/Yb)Nratios indicate that plagioclase and amphibole are residual in the source, and garnet is absent, implying that the magma was generated at low levels of pressure. By contrast, the contemporaneous granites in the SE Xing'an Block suggest a subduction-related tectonic setting, and its adakitic property indicates a thickened continental crust.We suggest that the Paleo-Asian Ocean plate between the Xing'an and Songnen blocks subducted northward during the Early Ordovician. Meanwhile, the NE Songnen Block was exposed to a passive continental margin tectonic setting. 展开更多
关键词 Early ORDOVICIAN a-type GRANITE Songnen and Xing’an BLOCKS GEODYNAMIC setting
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Effect of F-Rich Fluids on the A-Type Magmatism and Related Metal Mobilization:New Insights from the Fogang-Nankunshan-Yajishan Igneous Rocks in Southeast China 被引量:8
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作者 Xing Ding Koulin Su +2 位作者 Haibo Yan Jinlong Liang Weidong Sun 《Journal of Earth Science》 SCIE CAS CSCD 2022年第3期591-608,共18页
About 45%of tungsten,~20%of tin,and~9%of fluorite of known world reserves are associated with Late Mesozoic igneous rocks,Southeast(SE)China.Here we demonstrate that Fogang granite,the largest inland batholith,is main... About 45%of tungsten,~20%of tin,and~9%of fluorite of known world reserves are associated with Late Mesozoic igneous rocks,Southeast(SE)China.Here we demonstrate that Fogang granite,the largest inland batholith,is mainly of A2-type that is commonly found in post-orogenic settings and experienced plate subduction induced metasomatism.In contrast,the Yajishan syenite and Nankunshan granite intruding the Fogang granite~20 Ma later are of A1-type formed in intraplate settings.We found that F-rich fluid fractionation,which could make the decline of Ga/Al ratio,total(Nb+Y+Ce+Zr)and Zr concentrations,Nb/Ta and Zr/Hf ratios,leads to chemical variations of a few Fogang granites changing from A2-type to highly fractionated or I-and S-type granitoids.Crystal and Frich fluid fractionations,as well as crustal contamination most likely derived from the Fogang granite,result in some Nankunshan granites developing from A1-type into A2-type.These late-or post-magmatic processes should be taken into account carefully when discriminating the petrogenetic types of igneous rocks,especially for the A2-type suites.Combining with the distribution of 180-140 Ma A1-and A2-type igneous rocks,rare metal deposits,and fluorite deposits in SE China,we highlight the significant role of slab-released F-rich fluids in formation of A-type suites and subsequent chemical differentiation and rare metal and fluorine mineralization.A model of flat-slab northeastward rollback is thus proposed,in which the subduction front reached somewhere near Fogang and then started to roll back at~165 Ma.The inland Jurassic granites of SE China represent a unique locality for formation of A-type suites and their associated mineralization.These granites are not anorogenic,but they are the result of slab rollback from a flat slab,founding of that slab at shallow levels,and metasomatism of by F-rich fluids related to slab heating by the asthenosphere. 展开更多
关键词 a-type granite alkaline F-rich fluids slab rollback rare metal rare earth elements Nb/Ta
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Zircon SHRIMP U-Pb Ages,Geochemistry and Nd-Hf Isotopes of~1.0 Ga A-Type Felsic Rocks in the Southwestern Yangtze Block,South China:Petrogenesis and Tectonic Implications 被引量:6
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作者 Ji-Biao Zhang Xiao-Zhong Ding Yan-Xue Liu 《Journal of Earth Science》 SCIE CAS CSCD 2023年第2期504-517,共14页
The petrogenesis and tectonic affinity of Late Mesoproterozoic igneous rocks in the Yangtze Block are important to understand its tectonic evolution within the context of the Rodinia supercontinent’s reconstruction.H... The petrogenesis and tectonic affinity of Late Mesoproterozoic igneous rocks in the Yangtze Block are important to understand its tectonic evolution within the context of the Rodinia supercontinent’s reconstruction.Here,we report the SHRIMP zircon U-Pb ages,geochemistry,and Nd-Hf isotopic data for dacite from the Zegu Formation of the Dengxiangying Group in southwestern Yangtze Block.The crystallization age of the Zegu dacite is 1037 Ma.These rocks have relatively high Ga,Zr,Hf,and HREE contents,as well as high(10000×Ga)/Al(2.7-2.9)and FeOt/MgO(3.8-10.5)ratios,showing a geochemical affinity of A-type granitoids.Moreover,they are characterized by negativeεNd(t)(-3.6 to-7.5)and zirconεHf(t)values(-0.3 to-14.4),indicating that they likely generated via partial melting of an ancient continental crust source.The tectonic discriminant diagrams showed that the Zegu dacites have high Y and Nb contents(plotted in the‘within-plate’magmatic rocks field).In conclusion,the geochemistry and isotopic data indicated that the 1037 Ma felsic volcanic rock in the Dengxiangying Group generated during an intra-plate rift basin along a passive margin.Our work thus argues against a Grenvillian orogen’s existence in the Yangtze Block.In view of the subsequent Neoproterozoic subduction-related magmatism in the region,we suggest that the Yangtze Block might have been along the periphery of the Rodinia. 展开更多
关键词 a-type granotoids zircon SHRIMP U-Pb dating intra-plate magmatism Late Mesoproterozoic Southwestern Yangtze Block GEOCHEMISTRY
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