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Chemical looping reforming of the micromolecular component from biomass pyrolysis via Fe_(2)O_(3)@SBA-16
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作者 Yunchang Li Bo Zhang +3 位作者 Xiantan Yang Bolun Yang Shengyong Zhang Zhiqiang Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期120-134,共15页
To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling s... To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming. 展开更多
关键词 Biomass pyrolysis METHANE chemical looping reforming Oxygen carrier Kinetic analysis
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Engineering the coordination structure of Cu for enhanced photocatalytic production of C_(1) chemicals from glucose
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作者 Lulu Sun Shiyang Liu +3 位作者 Taifeng Liu Dongqiang Lei Nengchao Luo Feng Wang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期234-243,共10页
Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars wi... Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars with concurrent production of H_(2),which remains challenging.Here,the photo-catalytic activity for glucose decomposition to HCOOH,CO(C_(1) chemicals),and H_(2) on Cu/TiO_(2)was enhanced by nitrogen doping.Owing to nitrogen doping,atomically dispersed and stable Cu sites resistant to light irradiation are formed on Cu/TiO_(2).The electronic interaction between Cu and nitrogen ions originates valence band structure and defect levels composed of N 2p orbit,distinct from undoped Cu/TiO_(2).Therefore,the lifetime of charge carriers is prolonged,resulting in the pro-duction of C_(1) chemicals and H_(2) with productivities 1.7 and 2.1 folds that of Cu/TiO_(2).This work pro-vides a strategy to design coordinatively stable Cu ions for photocatalytic biomass conversion. 展开更多
关键词 Cu photocatalyst Coordination structure BIOMASS C−C bond C_(1) chemicals
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Preparation and Characterization of Activated Carbons from Palm Nut Shells: Effects of Calcination Temperature on Porosity and Chemical Properties
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作者 Charly Mve Mfoumou Berthy Lionel Mbouiti +2 位作者 Spenseur Bouassa Mougnala Pradel Tonda-Mikiela Guy Raymond Feuya Tchouya 《Open Journal of Inorganic Chemistry》 2024年第2期19-32,共14页
Activated carbons (ACs) calcined at 400˚C, 500˚C, and 600˚C (AC-400, AC-500, and AC-600) were prepared using palm nut shells from Gabon as raw material and zinc chloride (ZnCl2) as a chemical activating agent. Prepare... Activated carbons (ACs) calcined at 400˚C, 500˚C, and 600˚C (AC-400, AC-500, and AC-600) were prepared using palm nut shells from Gabon as raw material and zinc chloride (ZnCl2) as a chemical activating agent. Prepared ACs were characterized by physisorption of nitrogen (N2), determination of diode and methylene blue numbers for studies of porosity and by quantification and determination of surface functional groups and pH at point of zero charge (pHpzc) respectively, for studies of chemical properties of prepared ACs. Then, effects of calcination temperature (Tcal) on porosity and chemical properties of prepared ACs were studied. The results obtained showed that when the calcination temperature increases from 500˚C to 600˚C, the porosity and chemical properties of prepared ACs are modified. Indeed, the methylene blue and iodine numbers determined for activated carbons AC-400 (460 and 7.94 mg·g−1, respectively) and AC-500 (680 and 8.90 mg·g−1, respectively) are higher than those obtained for AC-600 (360 and 5.75 mg·g−1, respectively). Compared to the AC-500 adsorbent, specific surface areas (SBET) and microporous volume losses for AC-600 were estimated to 44.7% and 45.8%, respectively. Moreover, in our experimental conditions, the effect of Tcal on the quantities of acidic and basic functional groups on the surface of the ACs appears negligible. In addition, results of the pHpzc of prepared ACs showed that as Tcal increases, the pH of the adsorbents increases and tends towards neutrality. Indeed, a stronger acidity was determined on AC-400 (pHpzc = 5.60) compared to those on AC-500 and AC-600 (pHpzc = 6.85 and 6.70, respectively). Also according to the results of porosity and chemical characterizations, adsorption being a surface phenomenon, 500˚C appears to be the optimal calcination temperature for the preparation of activated carbons from palm nut shells in our experimental conditions. 展开更多
关键词 Palm Nut Shells Activated Carbon Calcination Temperature Porosity and chemical Properties
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Physicochemical Characterisation of Flours from Local Cereals and Powder from Cassava (Manihot esculenta Crantz) Leaves Varieties Cultivated in the Northern-Cameroon in Order to Supplement Infant Flours
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作者 Mathieu Barbi Charles Touwang +2 位作者 Emmanuel Panyoo Akdowa Augustin Goudoum Armand Abdou Bouba 《Open Journal of Applied Sciences》 2024年第8期2009-2026,共18页
The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. I... The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. In this paper, a A survey to identify the cereals used in the preparation of infant porridge in the Northern Cameroon was done by using 447 mothers having children between 06 and 59 months from areas (Gbakoungue, Sassa-Mbersi, Sanguere-Ngal and Kotkong-Wouldata) with high rate on malnourished children. Flour was prepared from the most preponderant cereals and Cassava leaves powder from varieties identified by the Regional Centre of Agricultural Research (CRRA) of Wakwa and local population. Flour and powder samples obtained were subjected to chemical composition analysis. Parameters analysed were crude proteins, total carbohydrates, ash, total fats, total phenols, total tannins, total carotenoids, vitamin C or cyanide. Also Iron, calcium and zinc were determined. The results revealed that white maize (62%) was the main cereal used in the preparation of infant porridge followed respectively by red sorghum, white rice and muskwari. Ten cassava varieties were identified: three (03) by CRRA (TME, 96/1/14 and IRAD 4115) and seven (south, gambada, sweet, Benin, six months, M. glaziovii and grouna) by local population. Amongst cereals flour, those from white maize indicated high protein (10.09%), carbohydrates (84.46%) and total fat (7.46%) contents. The powder from 96/14/14 cassava variety showed high amount of iron (11.98 mg/100g), calcium (751.02 g/100g) and low cyanide content (1.21 ppm) amongst all the cassava leaves powder samples. The supplementation of white maize flour by cassava leaves powder from 96/14/14 variety could therefore be recommended for the preparation of infant flours. 展开更多
关键词 Infant Flour Cereals Flour Cassava Leaves Powder chemical Composition Northern Cameroon
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Comparative Study of Physico-Chemical and Biological Water Quality Upstream and Downstream of the Manantali Dam and Hydropower Plant from 2019 to 2023
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期111-131,共21页
The comparative study is designed to monitor the physico-chemical and biological quality of the water upstream and downstream of the Manantali hydroelectric dam. The physico-chemical parameters are sampled at 3 measur... The comparative study is designed to monitor the physico-chemical and biological quality of the water upstream and downstream of the Manantali hydroelectric dam. The physico-chemical parameters are sampled at 3 measuring points located at Station 1 of the dam’s reservoir, immediately downstream of the dam and hydroelectric power station at the level of the damping basin, and at the Bafing-Bakoye confluence at Bafoulabe (Bafing side), the biological parameter (ichthyological fauna) is characterized by ichthyological inventories of landings in the various fishing camps around the reservoir and at the Mahina market (Bafing side). The study assesses the environmental impact of hydroelectric structures and facilities on the physico-chemical and biological quality of the water. Physical parameters such as temperature, conductivity, pH, turbidity and chemical parameters such as dissolved oxygen, nitrite, nitrate, manganese, hydrogen sulfide, ammonium, iron, silica and phosphorus are measured in order to identify the various variations existing between the different measurement points. Analysis of the values obtained shows very high similarities between the various measuring points, and most parameters comply with WHO standards, with the exception of turbidity, manganese, hydrogen sulfide and iron. These data attest to good water quality, allowing normal development of flora and fauna with a low level of degradation. Comparative analysis of the ichthyological fauna shows the existence of 34 species of fish belonging to 11 families at the fishing camps around the Manantali dam reservoir, and 37 species belonging to 12 families at Mahina on the Bafing River. At Mahina on the Bafing, the specific composition of the catches is characterized by the presence of the Claroteidae family and four species (Alestes sp., Brycinus leuciscus, Auchenoglanis occidentalis, Distichodus engycephalus) not recorded at the camps. In contrast, all the fish families recorded in the camps are present in Mahina, and only one species (Hydrocynus brevis) is absent from the Mahina landings. The difference in species richness could be explained by the upwelling of some fish from the Bakoye to the Bafing at the confluence. The Shannon diversity index of 4.07 at Mahina is higher than the 2.98 recorded at camp level, and the equitability index of 0.78 at Mahina and 0.58 at the camp level indicate average diversity and the non-dominance of one species over the others. The diversification index values of 3.09 and 3.08 at camp level and Mahina respectively show that the number of theoretical habitats is three. 展开更多
关键词 Manantali Dam Physical Parameters chemical Parameters Fish Fauna
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Vegetable Oil-Based Nanolubricants in Machining:From Physicochemical Properties to Application 被引量:6
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作者 Xiaotian Zhang Changhe Li +9 位作者 Zongming Zhou Bo Liu Yanbin Zhang Min Yang Teng Gao Mingzheng Liu Naiqing Zhang Zafar Said Shubham Sharma Hafiz Muhammad Ali 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期4-42,共39页
Cutting fluid is crucial in ensuring surface quality and machining accuracy during machining.However,traditional mineral oil-based cutting fluids no longer meet modern machining’s health and environmental protection ... Cutting fluid is crucial in ensuring surface quality and machining accuracy during machining.However,traditional mineral oil-based cutting fluids no longer meet modern machining’s health and environmental protection require-ments.As a renewable,pollution-free alternative with excellent processing characteristics,vegetable oil has become an inevitable replacement.However,vegetable oil lacks oxidation stability,extreme pressure,and antiwear proper-ties,which are essential for machining requirements.The physicochemical characteristics of vegetable oils and the improved methods’application mechanism are not fully understood.This study aims to investigate the effects of viscosity,surface tension,and molecular structure of vegetable oil on cooling and lubricating properties.The mechanisms of autoxidation and high-temperature oxidation based on the molecular structure of vegetable oil are also discussed.The study further investigates the application mechanism and performance of chemical modification and antioxidant additives.The study shows that the propionic ester of methyl hydroxy-oleate obtained by epoxidation has an initial oxidation temperature of 175℃.The application mechanism and extreme pressure performance of conventional extreme pressure additives and nanoparticle additives were also investigated to solve the problem of insufficient oxidation resistance and extreme pressure performance of nanobiological lubricants.Finally,the study discusses the future prospects of vegetable oil for chemical modification and nanoparticle addition.The study provides theoretical guidance and technical support for the industrial application and scientific research of vegetable oil in the field of lubrication and cooling.It is expected to promote sustainable development in the manufacturing industry. 展开更多
关键词 Cutting fluid Vegetable oil chemical modification ANTIOXIDANT Extreme pressure additive Minimum quality lubrication
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Extraction and analysis of risk factors from Chinese chemical accident reports 被引量:1
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作者 Xi Luo Xiayuan Feng +4 位作者 Xu Ji Yagu Dang Li Zhou Kexin Bi Yiyang Dai 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期68-81,共14页
Accidents in chemical production usually result in fatal injury,economic loss and negative social impact.Chemical accident reports which record past accident information,contain a large amount of expert knowledge.Howe... Accidents in chemical production usually result in fatal injury,economic loss and negative social impact.Chemical accident reports which record past accident information,contain a large amount of expert knowledge.However,manually finding out the key factors causing accidents needs reading and analyzing of numerous accident reports,which is time-consuming and labor intensive.Herein,in this paper,a semiautomatic method based on natural language process(NLP)technology is developed to construct a knowledge graph of chemical accidents.Firstly,we build a named entity recognition(NER)model using SoftLexicon(simplify the usage of lexicon)+BERT-Transformer-CRF(conditional random field)to automatically extract the accident information and risk factors.The risk factors leading to accident in chemical accident reports are divided into five categories:human,machine,material,management,and environment.Through analysis of the extraction results of different chemical industries and different accident types,corresponding accident prevention suggestions are given.Secondly,based on the definition of classes and hierarchies of information in chemical accident reports,the seven-step method developed at Stanford University is used to construct the ontology-based chemical accident knowledge description model.Finally,the ontology knowledge description model is imported into the graph database Neo4j,and the knowledge graph is constructed to realize the structu red storage of chemical accident knowledge.In the case of information extraction from 290 Chinese chemical accident reports,SoftLexicon+BERT-Transformer-CRF shows the best extraction performance among nine experimental models.Demonstrating that the method developed in the current work can be a promising tool in obtaining the factors causing accidents,which contributes to intelligent accident analysis and auxiliary accident prevention. 展开更多
关键词 chemical processes chemical process safety Natural language process Knowledge graph Neural networks Algorithm
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Numerical Simulation of Thermo-Hydro-Mechanical-Chemical Response Caused by CO_(2)Injection into Saline Geological Formations:A Case Study from the Ordos Project,China 被引量:1
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作者 FAN Zejin XU Tianfu +2 位作者 YANG Bo ZHANG Hui ZHU Huixing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第3期889-910,共22页
Thermo-hydro-mechanical-chemical(THMC)interactions are prevalent during CO_(2)geological sequestration(CGS).In this study,a sequential coupling THMC numerical simulation program was constructed,which can be used to ex... Thermo-hydro-mechanical-chemical(THMC)interactions are prevalent during CO_(2)geological sequestration(CGS).In this study,a sequential coupling THMC numerical simulation program was constructed,which can be used to explore the following issues of CGS:fluid and heat flow,solute transport;stresses,displacements and rock failures related to geo-mechanical effects;equilibrium and kinetic chemical reactions;chemical damage to mechanical properties of the rock.Then,the coupling program was applied to the Ordos CGS Project to study the formation response under the multifield interaction caused by CO_(2)injection.The simulation results show that the mechanical process dominates the short CO_(2)injection period.Specifically,the formation’s permeability near the injection well increases by 43%,due to the reduction of effective stress,which significantly promotes the lateral migration of CO_(2).When the injection rate exceeds 0.15 million tons per year,the cohesion of the reservoir rock is not enough to resist the shear force inside the rock and rock failure may occur.During the subsequent long-term sequestration period(200 years),the influence of mineral reactions gradually increases.Due to calcite dissolution,the shear modulus of caprock is predicted to decrease by 7.6%,which will to some extent increase the risk of rock failure. 展开更多
关键词 CO_(2) geological sequestration THMC coupling numerical simulation chemical damage
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The Adsorption of Pb(II)Using Silica Gel Synthesized from Chemical Bottle Waste:Optimization Using Box-Behnken Design 被引量:1
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作者 Yatim Lailun Ni’mah Nabila Eka Yuningsih Suprapto Suprapto 《Journal of Renewable Materials》 SCIE EI 2023年第6期2913-2924,共12页
The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)r... The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)removal from water was evaluated and optimized using the Response Surface Methodology(RSM).Under optimized conditions(adsorbent dose:20 mg;contact time:30 min;initial Pb(II)concentration:120 mg.L^(−1);and pH:8),the removal of Pb(II)was 99.77%.The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm models.The Langmuir isotherm model fits the experimental data.This shows that the surface of the silica gel synthesized from chemical bottles waste was covered by a Pb(II)monolayer.XRF analysis showed that the synthesized silica gel had a SiO_(2) content of 75.63%.Amorphous silica was observed from XRD analysis.SEM-EDX characterization showed that Pb was adsorbed on the silica gel surface.SEM analysis showed that silica gel has irregular particles with a surface area of 297.08 m2.g^(−1) with a pore radius of 15.74 nm calculated from BET analysis. 展开更多
关键词 chemical bottle waste silica gel ADSORPTION box-behnken design response surface methodology
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Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner 被引量:2
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作者 Bihui Hong Wenbin Li +2 位作者 Yiming Li Zhiwei Guo Binyou Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期374-385,共12页
This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double... This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner. 展开更多
关键词 Shaped charge chemical vapor deposition TUNGSTEN Double-layer charge liner X-ray PENETRATION
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A novel method for simulating nuclear explosion with chemical explosion to form an approximate plane wave: Field test and numerical simulation 被引量:1
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作者 Wei Ming Xiaojie Yang +3 位作者 Yadong Mao Xiang Wang Manchao He Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2137-2153,共17页
A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection infrastructures.With the increase in... A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection infrastructures.With the increase in nuclear explosion power,underground protection engineering enabled by explosion-proof impact theory and technology ushered in a new challenge.This paper proposes to simulate nuclear explosion tests with on-site chemical explosion tests in the form of multi-hole explosions.First,the mechanism of using multi-hole simultaneous blasting to simulate a nuclear explosion to generate approximate plane waves was analyzed.The plane pressure curve at the vault of the underground protective tunnel under the action of the multi-hole simultaneous blasting was then obtained using the impact test in the rock mass at the site.According to the peak pressure at the vault plane,it was divided into three regions:the stress superposition region,the superposition region after surface reflection,and the approximate plane stress wave zone.A numerical simulation approach was developed using PFC and FLAC to study the peak particle velocity in the surrounding rock of the underground protective cave under the action of multi-hole blasting.The time-history curves of pressure and peak pressure partition obtained by the on-site multi-hole simultaneous blasting test and numerical simulation were compared and analyzed,to verify the correctness and rationality of the formation of an approximate plane wave in the simulated nuclear explosion.This comparison and analysis also provided a theoretical foundation and some research ideas for the ensuing study on the impact of a nuclear explosion. 展开更多
关键词 Approximate plane wave Multi-hole simultaneous blasting chemical explosion Nuclear explosion Pressure sensor inclusion
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Chemical looping conversion of methane via Fe_(2)O_(3)-LaFeO_(3)calcined from LaFe-MOF precursor
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作者 Jitong Deng Yongjun Zhang +6 位作者 Xiaopeng Wang Wei Zhang Hongjing Han Haiying Wang Huimin Yuan Yanan Zhang Yanguang Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第10期225-237,共13页
The effective utilization of natural gas resources is a promising option for the implementation of the"dual carbon"strategy.However,the capture of carbon dioxide with relatively lower concentration after the... The effective utilization of natural gas resources is a promising option for the implementation of the"dual carbon"strategy.However,the capture of carbon dioxide with relatively lower concentration after the combustion of natural gas is the crucial step.Fortunately,the lattice oxygen is used for chemical cycle conversion of methane to overcome the shortcomings mentioned above.A method was proposed to synthesize perovskite for methane cycle conversion using metal organic framework as a precursor.Morphology and pore structure of Fe_(2)O_(3)-LaFeO_(3)composite oxides were regulated by precursor synthesis conditions and calcination process.Moreover,the chemical looping conversion performance of methane was evaluated.The results showed that the pure phase precursor of La[Fe(CN)_(6)]·5H_(2)O was synthesized with the specific surface area of 23.91 m^(2)·g^(-1)under the crystallization of 10 h and the pH value of10.5.Fe_(2)O_(3)-LaFeO_(3)was obtained by controlled calcination of La[Fe(CN)_(6)]·5H_(2)O and Fe_(2)O_(3)with variable mass ratio.The selectivity of CO_(2)can reach more than 99%under the optimal parameters of methane chemical looping conversion:m(Fe_(2)O_(3)):m(LaFeO_(3))=2:1,the reaction temperature is 900℃,the lattice oxygen conversion is less than 40%.Fe_(2)O_(3)-LaFeO_(3)still has good phase and structure stability after five redox reaction and regeneration cycles. 展开更多
关键词 COMPOSITE chemical looping conversion Carbon dioxide Metal organic frameworks Lattice oxygen METHANE
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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:1
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials
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Chemical Constituents from Ethnic Medicine Laportea bulbifera
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作者 Ao XIE Yongjing SU +4 位作者 Wenya LI Junmiao MO Wenwen LIANG Haicheng WEN Chen LIN 《Agricultural Biotechnology》 CAS 2023年第1期47-48,52,共3页
[Objectives]This study was conducted to study the chemical constituents from Laportea bulbifera. [Methods] The 60% ethanol extract from L. bulbifera was isolated and purified by silica, Sephadex LH-20, ODS, semi-prepa... [Objectives]This study was conducted to study the chemical constituents from Laportea bulbifera. [Methods] The 60% ethanol extract from L. bulbifera was isolated and purified by silica, Sephadex LH-20, ODS, semi-preparative HPLC and recrystallization. Their chemical structures were elucidated by physicochemical properties and spectroscopic methods. [Results] These compounds were determined as kaempferol-3-O-α-L-(3-O-acetyl)-rhamnoside-7-O-α-L-rhamnoside(1), sutchuenoside A(2), kaempferol-3-O-[β-D-glucopyranosyl-(1→3)]-α-L-(4-O-acetyl)-rhamnopyranoside-7-O-α-L-rhamnopyranoside(3). Compounds 1-3 are isolated from genus Laportea for the first time. Compound 3 is a new compound. [Conclusions] This study lays a foundation for improving the quality standard of L. bulbifera and the development and utilization of its resources. 展开更多
关键词 Ethnic medicine Laportea bulbifera chemical constituents Structural identification
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Study on Chemical Constituents from Phellodendron chinense
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作者 Lian LIAN Xiaoyan XIAN +2 位作者 Donghai CHU Weili JIA Huiyuan GAO 《Medicinal Plant》 CAS 2023年第2期5-7,共3页
[Objectives]To isolate and identify chemical constituents from Phellodendron chinense.[Methods]Compounds were isolated by silica gel,Sephadex LH-20,and ODS column chromatography,and their structures were determined by... [Objectives]To isolate and identify chemical constituents from Phellodendron chinense.[Methods]Compounds were isolated by silica gel,Sephadex LH-20,and ODS column chromatography,and their structures were determined by means of the spectral analysis and physicochemical properties.[Results]Eleven compounds were isolated and identified as berberine(1),obaculactone(2),shihulimonin A(3),N-p-coumaroyltyramine(4),1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-propyl)-2-methoxyphenoxy]-propane-1,3-diol(5),phellodendrine(6),magnoflorine(7),palmatine(8),jatrorrhizine(9),columbamine(10),and obacunone(11).[Conclusions]Compounds 3 and 5 were isolated from Phellodendron for the first time,and compound 4 was isolated from this plant for the first time. 展开更多
关键词 Phellodendron chinense chemical constituents Structural identification Isolated for the first time
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Preparation and Characterization of Activated Carbons from Asparagus Palm (Laccosperma robustum) Bark by Chemical Activation with H3PO4 and KOH
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作者 Phil Lewis Mpampoungou Langama Jean Jacques Anguile +4 位作者 Crislain Bissielou Adam Bouraïma Albert Novy Messi Me Ndong Daouda Kouotou Joseph Ketcha Mbadcam 《American Journal of Analytical Chemistry》 CAS 2023年第2期55-71,共17页
The present work deals with the preparation and characterization of activated carbons from the bark of the asparagus palm (Laccosperma robustum) by chemical activation with phosphoric acid and potassium hydroxide. The... The present work deals with the preparation and characterization of activated carbons from the bark of the asparagus palm (Laccosperma robustum) by chemical activation with phosphoric acid and potassium hydroxide. The process was optimized on the basis of the analysis of the iodine number, methylene blue number and activated carbons yield as a function of the preparation parameters (concentration of the activating agents and the pyrolysis temperature). It emerges that the pyrolysis temperature and the concentration of activating agents influence the activated carbons preparation process. Their values were 500°C and 20% respectively for activated carbon with H<sub>3</sub>PO<sub>4</sub> (ACP) and 700°C and 1.5% for activated carbon with KOH (ACK). The iodine numbers obtained were 850.26 mg/g for ACP and 865.49 mg/g for ACK. The methylene blue numbers obtained were 149.35 mg/g for ACP and 149.25 mg/g for ACK. The activated carbons yields obtained were 25% for ACP and 5.9% for ACK. The activated carbons prepared under optimal conditions have shown the pH of zero-point charge (pHzpc) of 4.4 and 7.0 for ACP for ACK respectively. The determination of the surface functions revealed that ACP had a strong acidic character while ACK had neutral character. The Fourier transformed infrared spectroscopy also showed the presence of different functional groups on the surface of the precursor and activated carbons. 展开更多
关键词 Activated Carbons Asparagus Palm Bark chemical Activation Phosphoric Acid Potassium Hydroxide
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The main chemical constituents from Piper amalago: A review of its phytochemistry
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作者 Zhaojun Zhang Zhikang Duan Xiaoxiao Huang 《Asian Journal of Traditional Medicines》 2023年第3期98-115,共18页
Piper amalago(P.amalago)is a traditional medicine in Brazil for the treatment of leishmanial.Owing to its rare occurrence and potent pharmacological activities,efforts have been devoted to the identification of its di... Piper amalago(P.amalago)is a traditional medicine in Brazil for the treatment of leishmanial.Owing to its rare occurrence and potent pharmacological activities,efforts have been devoted to the identification of its diverse constituents,especially terpenoids.Researchers have found that the major constituents of P.amalago were amides,monoterpenes,norisoprenoids,sesquiterpenes,aliphatic hydrocarbons and aromatic hydrocarbons.The amides show anxiolytic,anti-inflammatory,antileishmanial and antinociceptive activity.This review summarizes the research progress of the structural diversity and pharmacological activities of P.amalago. 展开更多
关键词 Piper amalago chemical constituents pharmacological effects research review
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Chemical composition and biological activities of volatile oil isolated from Curcumae rhizoma
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作者 Wenhan Wang Yibo Wang +3 位作者 Yuntian Xing Xinyao Wang Guanyi Zhao Yu Chen 《Asian Journal of Traditional Medicines》 2023年第6期280-288,共9页
Curcumae rhizoma(C.rhizoma),the rhizome of Curcuma Longa L.,Curcuma kwangsiensis L.and Curcuma wenyujin L.in the ginger family,is a treasure in traditional Chinese medicine.It has the effect of promoting qi and breaki... Curcumae rhizoma(C.rhizoma),the rhizome of Curcuma Longa L.,Curcuma kwangsiensis L.and Curcuma wenyujin L.in the ginger family,is a treasure in traditional Chinese medicine.It has the effect of promoting qi and breaking blood,eliminating accumulation and relieving pain.With the development of modern medicine,the active ingredients and therapeutic mechanism of C.rhizoma have been gradually revealed.In this paper,the chemical composition and biological activities of volatile oil isolated from C.rhizoma are reviewed in detail,aiming to provide reference for further utilization of C.rhizoma volatile oil and provide more effective drug options for clinical treatment. 展开更多
关键词 Curcumae rhizoma chemical composition biological activity
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Soil Chemical Property Changes over Time from Struvite Compared to Other Fertilizer-Phosphorus Sources in Multiple Soils
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作者 Tatum Simms Kristofor R. Brye +1 位作者 Trenton L. Roberts Lauren F. Greenlee 《Agricultural Sciences》 2023年第10期1465-1500,共36页
Studies have shown that phosphorus (P) recovered from wastewater as the mineral struvite [MgNH<sub>4</sub>PO<sub>4</sub>·6(H<sub>2</sub>O)] may be a viable alternative fertiliz... Studies have shown that phosphorus (P) recovered from wastewater as the mineral struvite [MgNH<sub>4</sub>PO<sub>4</sub>·6(H<sub>2</sub>O)] may be a viable alternative fertilizer-P source. This study aimed to compare the effectiveness of electrochemically precipitated struvite (ECST), reclaimed from synthetic wastewater, to other commercial fertilizer-P sources in cultivated soils from Arkansas [AR;silt loam (SiL) and loam (L)], Missouri (MO;SiL), and Nebraska [NE;SiL and sandy loam (SL)]. A plant-less, moist-soil incubation experiment, including ECST, chemically precipitated struvite (CPST), monoammonium phosphate (MAP), triple superphosphate (TSP), and an unamended control (UC), was conducted to quantify soil pH, nitrate (NO<sub>3</sub>-N), ammonium (NH<sub>4</sub>-N), and Mehlich-3 (M3)-P, -Ca, -Mg, and -Fe concentrations at 0.5, 1, 2, 4, and 6 months. All measured soil properties differed (P ·kg<sup>-1</sup> for AR-L-TSP after 1 month and NE-SiL-MAP after 6 months, respectively. Soil M3-P ranged from -29.6 mg·kg<sup>-1</sup> in the AR-L-UC after 1 month to 429 mg·kg<sup>-1</sup> AR-SiL-TSP after 0.5 months. Results showed that, over time, ECST had comparable pH and soil NO<sub>3</sub>-N, NH<sub>4</sub>-N, and M3-P, -Ca, -Mg, and -Fe behavior compared to CPST, MAP, and TSP across various soil textures. 展开更多
关键词 Electrochemically Precipitated Struvite chemically Precipitated Struvite Soil Incubation Soil Texture
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Rational design of F,N-rich artificial interphase via chemical prelithiation initiation strategy enabling high coulombic efficiency and stable micro-sized SiO anodes
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作者 Quanyan Man Hengtao Shen +3 位作者 Chuanliang Wei Baojuan Xi Shenglin Xiong Jinkui Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期224-232,共9页
Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid ... Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid electrolyte interface(SEI),which induce low energy,short cycling life,and poor rate properties.To address these drawbacks of SiO,we achieve in-situ construction of robust and fast-ion conducting F,N-rich SEI layer on prelithiated micro-sized SiO(P-μSiO)via the simple and continuous treatment ofμSiO in mild lithium 4,4′-dimethylbiphenyl solution and nonflammable hexafluorocyclotriphosphazene solution.Chemical prelithiation eliminates irreversible capacity through pre-forming inactive lithium silicates.Meanwhile,the symbiotic F,N-rich SEI with good mechanical stability and fast Li^(+)permeability is conductive to relieve volume expansion ofμSiO and boost the Li+diffusion kinetics.Consequently,the P-μSiO realizes an impressive electrochemical performance with an elevated ICE of 99.57%and a capacity retention of 90.67%after 350 cycles.Additionally,the full cell with P-μSiO anode and commercial LiFePO_(4) cathode displays an ICE of 92.03%and a high reversible capacity of 144.97 mA h g^(-1).This work offers a general construction strategy of robust and ionically conductive SEI for advanced LIBs. 展开更多
关键词 chemical prelithiation Silicon monoxide SEI Lithium-ion batteries INTERPHASE engineering
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