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Natural products and extracts from plants as natural UV filters for sunscreens:A review
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作者 Liyan Li Lan Chong +3 位作者 Tao Huang Yunge Ma Yingyan Li Hui Ding 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第3期183-195,共13页
Although solar exposure is necessary for human health,phototoxicology induced by excessive UVB and UVA radiation,which involves sunburns,skin aging and even tu-morigenesis,has been widely researched.Sunscreen is one o... Although solar exposure is necessary for human health,phototoxicology induced by excessive UVB and UVA radiation,which involves sunburns,skin aging and even tu-morigenesis,has been widely researched.Sunscreen is one of the most important ways to protect skin from UV phototoxic damage.As well as inorganic and organic UV filters,some natural products or plant extracts with aromatic rings in their structures,such as flavonoids or polyphenols,can absorb UV to reduce sunburn,acting as a natu-ral UV filter;they also show antioxidant or/and anti-inflammatory activity.This could explain why,although there are no officially approval natural commercial sun-filters,more and more commercial sunscreen products containing plant extracts are avail-able on the market.Here we summarize articles focusing on natural UV filters from plant published in the last 6 years,selecting the most significant data in order to better understand the photoprotective activity of natural products and extracts from plants,including their major constituents and main biological effects,methods for evaluating UV radiation resistance,anti-UV radiation experimental models and anti-UV radiation mechanisms. 展开更多
关键词 ANTIOXIDANTS evaluation method natural products and extracts from plants natural UV filters SPF value
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Economic and entropy production evaluation of extractive distillation and solvent-assisted pressure-swing distillation by multi-objective optimization
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作者 Yao Wang Qing Ye +2 位作者 Jinlong Li Qingqing Rui Azhi Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期246-259,共14页
Extractive distillation(ED)and solvent-assisted pressure-swing distillation(SA-PSD)are both special distillation processes that perform good at separating pressure-insensitive azeotropes.However,few reported studies h... Extractive distillation(ED)and solvent-assisted pressure-swing distillation(SA-PSD)are both special distillation processes that perform good at separating pressure-insensitive azeotropes.However,few reported studies have compared the performance of the two processes.In this paper,ED processes with N-methylpyrrolidone(NMP)and dimethlac-etamide(DMCA)as entrainer,SA-PSD process with isopropyl-alcohol(IPA)as solvent and SA-PSD process with partial heat integration(PHI-PSD)are proposed to achieve high purity separation of a mixture of cyclohexane/2-butanol system.The optimal operating conditions of the processes are obtained after optimizing with NSGA-Ⅱ algorithm when total annual cost(TAC)and the entropy production of process are set as objectives.The optimal results show that the optimal PHI-PSD process has lower TAC by 28.7% and the lower entropy production by 39.5% than the optimal SA-PSD process while the ED process with NMP as entrainer has lower TAC by 50.9% and the lower entropy production by 56.1% than the optimal SA-PSD process.The optimal results show that the ED process with NMP as entrainer has the best economic and thermodynamic efficiency among the four proposed processes in this paper. 展开更多
关键词 extractive distillation Solvent-assisted pressure-swing distillation Entropy production NSGA-Ⅱalgorithm Computer simulation
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Combining Deep Learning with Knowledge Graph for Design Knowledge Acquisition in Conceptual Product Design
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作者 Yuexin Huang Suihuai Yu +4 位作者 Jianjie Chu Zhaojing Su Yangfan Cong Hanyu Wang Hao Fan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期167-200,共34页
The acquisition of valuable design knowledge from massive fragmentary data is challenging for designers in conceptual product design.This study proposes a novel method for acquiring design knowledge by combining deep ... The acquisition of valuable design knowledge from massive fragmentary data is challenging for designers in conceptual product design.This study proposes a novel method for acquiring design knowledge by combining deep learning with knowledge graph.Specifically,the design knowledge acquisition method utilises the knowledge extraction model to extract design-related entities and relations from fragmentary data,and further constructs the knowledge graph to support design knowledge acquisition for conceptual product design.Moreover,the knowledge extraction model introduces ALBERT to solve memory limitation and communication overhead in the entity extraction module,and uses multi-granularity information to overcome segmentation errors and polysemy ambiguity in the relation extraction module.Experimental comparison verified the effectiveness and accuracy of the proposed knowledge extraction model.The case study demonstrated the feasibility of the knowledge graph construction with real fragmentary porcelain data and showed the capability to provide designers with interconnected and visualised design knowledge. 展开更多
关键词 Conceptual product design design knowledge acquisition knowledge graph entity extraction relation extraction
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Quality of healing of gastric ulcers: Natural products beyond acid suppression 被引量:14
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作者 Napapan Kangwan Jong-Min Park +1 位作者 Eun-Hee Kim Ki Baik Hahm 《World Journal of Gastrointestinal Pathophysiology》 CAS 2014年第1期40-47,共8页
Gastric ulcer is a chronic disease featured with unexpected complications, including bleeding, stenosis and perforation, as well as a high incidence of recurrence. Clinical treatments for gastric ulcer have allowed th... Gastric ulcer is a chronic disease featured with unexpected complications, including bleeding, stenosis and perforation, as well as a high incidence of recurrence. Clinical treatments for gastric ulcer have allowed the rapid development of potent anti-ulcer drugs during the last several decades. Gastric ulcer healing is successful with conventional treatments including H2-receptor antagonists, and proton pump inhibitors(PPIs) have been essential for ulcer healing and prevention of complications. Additionally, Helicobacter pylori eradication therapy is effective in reducing ulcer recurrence and leads to physiological changes in the gastric mucosa which affect the ulcer healing process. However, in spite of these advancements, some patients have suf-fered from recurrence or intractability in spite of continuous anti-ulcer therapy. A new concept of the quality of ulcer healing(QOUH) was initiated that considers the reconstruction of the mucosal structure and its function for preventing ulcer recurrence. Although several gastroprotection provided these achievements of the QOUH, which PPI or other acid suppressants did not accomplish, we found that gastroprotection that originated from natural products, such as a newer formulation from either Artemisia or S-allyl cysteine from garlic, were very effective in the QOUH, as well as improving clinical symptoms with fewer side effects. In this review, we will introduce the importance of the QOUH in ulcer healing and the achievements from natural products. 展开更多
关键词 QUALITY of ulcer HEALING Natural products Gastric ULCERS Acid suppression S-allyl cysteine ARTEMISIA ISOPROPANOL extract
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Form Gene Clustering Method about Pan-Ethnic-Group Products Based on Emotional Semantic 被引量:6
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作者 CHEN Dengkai DING Jingjing +2 位作者 GAO Minzhuo MA Danping LIU Donghui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1134-1144,共11页
The use of pan-ethnic-group products form knowledge primarily depends on a designer's subjective experience without user participation. The majority of studies primarily focus on the detection of the perceptual deman... The use of pan-ethnic-group products form knowledge primarily depends on a designer's subjective experience without user participation. The majority of studies primarily focus on the detection of the perceptual demands of consumers from the target product category. A pan-ethnic-group products form gene clustering method based on emotional semantic is constructed. Consumers' perceptual images of the pan-ethnic-group products are obtained by means of product form gene extraction and coding and computer aided product form clustering technology. A case of form gene clustering about the typical pan-ethnic-group products is investigated which indicates that the method is feasible. This paper opens up a new direction for the future development of product form design which improves the agility of product design process in the era of Industry 4.0. 展开更多
关键词 emotional semantic pan-ethnic-group products gene extract gene coding form gene clustering
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In vitro cytotoxicity of Indonesian stingless bee products against human cancer cell lines 被引量:1
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作者 Paula M.Kustiawan Songchan Puthong +1 位作者 Enos T.Arung Chanpen Chanchao 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第7期549-556,共8页
Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indon... Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indonesia for cytotoxic activity against five human cancer cell lines(HepG2,SW620,ChaGo-1,KATO-Ⅲand BT474).Methods:All samples were extracted with methanol,and then subpartitioned with n-hexane and ethyl acetate.Each crude extract was screened at 20μg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Tn addition,four previously shown bioactive components from propolis(apigenin,cafieic acid phenyl ester,kaempferol and naringenin)and two chemotherapeutic drugs(doxorubicin and 5-fluorouracil)were used to evaluate the sensitivity of the cell lines.Results:Overall,crude extracts from propolis and honey had higher cytotoxic activities than bee pollen,but the activity was dependent upon the extraction solvent,bee species and cell line.Propolis extracts from T.incisa and Tarda apicalis showed the highest and lowest cytotoxic activity,respectively.Only the HepG2 cell line was broadly sensitive to the honey extracts.For pure compounds,doxorubicin was the most cytotoxic,the four propolis compounds the least,but the ChaGo-I cell line was sensitive to kaempferol at 10μg/mL and KATO-Ⅲwas sensitive to kaempferol and apigenin at 10μg/mL,.All pure compounds were effective against the BT474 cell line.Conclusions:Propolis from f,incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines.Further study is required,including the isolation and characterization of the active antiproliferative agent(s). 展开更多
关键词 ANTIPROLIFERATIVE activity BEE product Cancer cell lines Cytotoxicity Ethyl acetate extract N-HEXANE HONEY Methanol PROPOLIS
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Recent Advances in Separation of Bioactive Natural Products 被引量:7
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作者 任其龙 邢华斌 +4 位作者 鲍宗必 苏宝根 杨启炜 杨亦文 张治国 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期937-952,共16页
Bioactive natural products are a main source of new drugs,functional foods and food additives.The separation of bioactive natural products plays an important role in transformation and use of biomass.The isolation and... Bioactive natural products are a main source of new drugs,functional foods and food additives.The separation of bioactive natural products plays an important role in transformation and use of biomass.The isolation and purification of bioactive principle from a complex matrix is often inherent bottleneck for the utilization of natural products,so a series of extraction and separation techniques have been developed.This review covers recent advances in the separation of bioactive natural products with an emphasis on their solubility and diffusion coefficients,recent extraction techniques and isolation techniques.This overview of recent technological advances,discussion of pertinent problems and prospect of current methodologies in the separation of bioactive natural products may provide a driving force for development of novel separation techniques. 展开更多
关键词 天然产物 生物活性 分离技术 提取技术 食品添加剂 功能食品 扩散系数 隔离技术
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Theory and practice of integrated coal production and gas extraction 被引量:65
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作者 Liang Yuan 《International Journal of Coal Science & Technology》 EI 2015年第1期3-11,共9页
关键词 煤炭生产 天然气开采 一体化 瓦斯抽采 提取系统 综合开采 水流条件 含煤盆地
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Mechanism and Clinical Observation of Effect of Growgx Yeast Fermentation Product Extract on Photo-aged HFF-1 Cells
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作者 Hong ZHANG Jianfei WAN +3 位作者 Yuetong ZHAO Yang WU Mingli LEI Xiaoqun DUAN 《Medicinal Plant》 CAS 2022年第1期26-29,共4页
[Objectives]To explore the effect of the extract of Growgx yeast fermentation product on ultraviolet A(UVA)-induced photo-aging of human skin fibroblasts(HFF-1)and its specific mechanisms from the level of cell biolog... [Objectives]To explore the effect of the extract of Growgx yeast fermentation product on ultraviolet A(UVA)-induced photo-aging of human skin fibroblasts(HFF-1)and its specific mechanisms from the level of cell biology,and discussed the application of the Growgx yeast fermentation product extract for skin aging.[Methods]A photo-aging model of HFF-1 cells was induced by UVA radiation meter,and it was given different concentrations of Growgx for intervention.The proliferation activity of the HFF-1 cells was detected with MTT method,and their migration and invasion ability was measured by scratch test.The SOD,HYP and MDA levels were detected with corresponding kits.After oxygen infusion apparatus assisted facial skin administration,the repair of the skin was observed through the VISIA skin tester.[Results]The survival rate of HFF-1 cells was reduced significantly by UVA with an irradiation dose of 10.8 J/cm2(P<0.05),while Growgx significantly increased their survival rate(P<0.001)and sped up the repair of damaged cells.Growgx promoted the production of SOD(P<0.05),reduced the level of MDA(P<0.05),and increased the level of HYP(P<0.05).Growgx effectively inhibited UVA-induced photo-aging of HFF-1 cells.The mechanism may be related to accelerating cell damage repair,up-regulating SOD and HYP expression levels,and reducing MDA expression level.The clinical observation showed that Growgx effectively improved skin spots and pores,making the skin smoother and more delicate.[Conclusions]Growgx can effectively fight against photo-aging caused by ultraviolet rays,and can significantly improve skin wrinkles. 展开更多
关键词 Growgx yeast fermentation product extract Human skin fibroblasts ANTI-AGING VISIA Clinical observation
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Effect of radiolysis of TODGA on the extraction of TODGA/n-dodecane toward Eu(Ⅲ):an experimental and DFT study
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作者 Hang Zhang Yin-Yong Ao +6 位作者 Yue Wang Shang-Jie Zhao Jia-Yang Sun Mao-Lin Zhai Jiu-Qiang Li Jing Peng Hui-Bo Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期1-13,共13页
N,N,N′,N′-Tetraoctyl diglycolamide(TODGA)is one of the most promising extractants tailored for high-level liquid radioactive waste treatment during nuclear fuel reprocessing.Theγ-radiolysis of TODGA(0.2 mol/L)in n-... N,N,N′,N′-Tetraoctyl diglycolamide(TODGA)is one of the most promising extractants tailored for high-level liquid radioactive waste treatment during nuclear fuel reprocessing.Theγ-radiolysis of TODGA(0.2 mol/L)in n-dodecane(n DD)solution with and without pre-equilibrated 3.0 mol/L HNO_(3)was investigated using HPLC and UPLC-QTOF-MS and compared with theγ-radiolysis of neat TODGA in this study.With increased absorbed doses,the concentration of TODGA decreased exponentially for the studied systems.Moreover,pre-equilibration with HNO_(3)(3.0 mol/L)slightly influenced theγ-radiolysis of TODGA in n DD.Seven radiolytic products generated from the rupture of the C–C,C–O,and C–N bonds in TODGA were identified in the studied extraction system.The influence ofγ-radiation on TODGA/n DD for the extraction of Eu(Ⅲ)was evaluated using the first combination of extraction experiments and density functional theory(DFT)calculations,in which the complexations of Eu(Ⅲ)with TODGA and its radiolytic products were systematically compared.Based on the radiolysis kinetic model of TODGA,the slope curve of the distribution ratio of Eu(Ⅲ)(D_(Eu))and the absorbed dose,and fluorescence titration analysis,the empirical equation of the absorbed dose and D_(Eu)was obtained successfully.Below 300 kGy,the experimental D_(Eu)agreed well with the obtained empirical equation for TODGA/n DD.Conversely,at a high absorbed dose,the experimental D_(Eu)was higher than the theoretical D_(Eu)based on the empirical equation because the radiolytic products of TODGA with similar coordination structures still possessed partial complexation toward Eu(Ⅲ),which was confirmed by DFT calculations.This work provides a method to predict the extraction distribution ratio of an irradiated extractant system and to understand the complex extraction process. 展开更多
关键词 TODGA Radiolytic products extractION Density functional theory COMPLEXATION
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β-Glucans: Characterization, Extraction Methods, and Valorization
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作者 Ana Chioru Aurica Chirsanova 《Food and Nutrition Sciences》 2023年第10期963-983,共21页
β-glucans are bioactive compounds with a wide range of biological properties, including anticancer, anti-inflammatory, antioxidant, and immune-modulating properties. Due to their specific physical properties, such as... β-glucans are bioactive compounds with a wide range of biological properties, including anticancer, anti-inflammatory, antioxidant, and immune-modulating properties. Due to their specific physical properties, such as (in)solubility, viscosity, and gelation, β-glucans are increasingly being used in the food, pharmaceutical, and cosmetic industries. The purpose of this review is to provide an overview of the different types of β-glucans, their sources, especially Saccharomyces cerevisiae yeasts, and the methods of extraction, isolation, and purification of β-glucans, with the aim of optimizing these methods for the efficient production process. Moreover, the physico-chemical properties, modifications, current applications and future prospects of the use of β-glucans in food, medicines, cosmetics and other potential value-added products are summarized. The data presented indicate that β-glucans will play an increasingly important role in the sector of special-purpose food products as well as in other current and future areas. 展开更多
关键词 β-Glucans YEAST extractION VALORIZATION Value-Added products
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Mercury Speciation of Flue Gas Desulphurization By-Products in Coal-Fired Power Plants in China
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作者 Gang Tian Hongyan Long +7 位作者 Yu Liu Chen Zhang Fan Zhang Hongchang Wang Jinwei Zhu Yanping Zhang Hongmei Wang Fan Wang 《Journal of Power and Energy Engineering》 2020年第11期1-11,共11页
The aim of this study was to develop and examine the morphology and distribution of mercury (Hg) in flue gas desulfurization (FGD) by-product.</span></span><span><span><span style="font... The aim of this study was to develop and examine the morphology and distribution of mercury (Hg) in flue gas desulfurization (FGD) by-product.</span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Mercury in the coal of coal-fired power plants is concentrated in the by-products of desulfurization process, and it is widely used as an additive in cement, building materials and other industries. Due to the different stability of various forms of mercury in the environment, subsequent use of products containing desulfurization by-product additives will continue to be released into the environment, endangering human health. Therefore, it is very necessary to study the form and distribution of mercury in the by-products of desulfurization in coal-fired power plants to provide a theoretical basis for subsequent harmless treatment.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">For content and morphology of mercury analysis, 1 sample of dry FGD ash and 6 samples of wet FGD gypsum were analyzed. The total 7 samples were extracted using a modification of sequential chemical extractions (SCE) method, which was employed for the partitioning Hg into four fractions: water soluble, acid soluble, H<sub>2</sub>O<sub>2</sub> soluble, and residual. The Hg analysis was done with United States Environmental Protection Agency (USEPA) method</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">7471B. Comparing with the wet FGD gypsums of coal-fired boilers, the total Hg content in the dry FGD by-product was as high as</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">1.22 mg/kg, while the total Hg content in the FGD gypsum is 0.23</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">0.74 mg/kg, which was 2 times over the wet FGD gypsum. The concentration of water soluble Hg in the dry FGD by-product was the highest amount (0.72 mg/kg), accounting for 59.02% of the total mercury. While residual Hg content was 0.16 mg/kg, only about 13.11% of the total mercury. Mercury content in FGD gypsum was expressed in the form of <i></span><i><span style="font-family:Verdana;">ρ</span></i><span style="font-family:Verdana;"></i></span></span></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">(residual Hg) ></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">ρ</span></i><span style="font-family:Verdana;"></i></span></span></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">(H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> soluble Hg)</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">ρ</span></i><span style="font-family:Verdana;"></i></span></span></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">(water soluble Hg)</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">ρ</span></i><span style="font-family:Verdana;"></i></span></span></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">(acid soluble Hg). The morphology and distribution of mercury in FGD by-products is supposed to be analyzed before utilization, and the impact of mercury on the environment should be considered. 展开更多
关键词 MERCURY Mercury Speciation Flue Gas DESULPHURIZATION BY-product Sequential Chemical extractions Morphology and Distribution GYPSUM
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月面原位水资源获取技术与发展趋势
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作者 张鹏 刘光辉 +7 位作者 刘欣 张光 郑海菠 代巍 王之 牛冉 薄正 高铭 《空间科学学报》 CAS CSCD 北大核心 2024年第2期309-317,共9页
随着深空探测活动的持续推进,月球探测已成为开展行星际探测的重要部分.月球原位资源利用是保障载人月球探测及月面长期驻留的关键技术途径,中国已将月面原位水获取方法列为月球探测的关键技术之一.月面原位水获取方法主要分为极区水冰... 随着深空探测活动的持续推进,月球探测已成为开展行星际探测的重要部分.月球原位资源利用是保障载人月球探测及月面长期驻留的关键技术途径,中国已将月面原位水获取方法列为月球探测的关键技术之一.月面原位水获取方法主要分为极区水冰勘探开采和月壤氢还原制水两种技术途径.现有勘探到的水冰资源主要位于月球极区,分布不均匀,开采难度大.目前研究提出了多种不同类型的极区水冰勘探开采方法,但实际效果有待月面原位试验验证.月壤加氢还原制水技术方法工作条件不受区域限制,应用范围较广,但仍存在反应条件要求高、能耗大等技术限制,未来需在节能和有效矿物成分富集等方面有所突破. 展开更多
关键词 月球探测 原位水获取 水冰提取 月壤氢还原
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非皂化P507体系萃取分离镧和锕元素
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作者 谈存敏 曹石巍 +2 位作者 黄清钢 陈德胜 秦芝 《核化学与放射化学》 CAS CSCD 北大核心 2024年第3期221-230,I0002,共11页
由于稀土生产过程中锕元素未被有效分离去除,导致我国部分稀土产品的放射性超出豁免值(α和β总放射性小于1 Bq/g)。本工作以非皂化的2-乙基己基磷酸单-2-乙基己基酯(P507)为萃取剂,二乙基三胺五乙酸(DTPA)或N-(2-羟乙基)乙二胺-N,N'... 由于稀土生产过程中锕元素未被有效分离去除,导致我国部分稀土产品的放射性超出豁免值(α和β总放射性小于1 Bq/g)。本工作以非皂化的2-乙基己基磷酸单-2-乙基己基酯(P507)为萃取剂,二乙基三胺五乙酸(DTPA)或N-(2-羟乙基)乙二胺-N,N',N'-三乙酸(HEDTA)为水相掩蔽剂,乳酸为酸度缓冲剂,分别在盐酸和硝酸体系中研究了对镧和锕两种元素的萃取分离。结果显示,弱酸试剂可有效缓冲稀土料液的酸度,使萃取反应向有利于生成有机配合物的方向进行。在pH为3.0、初始La^(3+)浓度为0.2 mol/L的盐酸溶液中,该体系对La^(3+)的萃取效果较单一的皂化P507有显著提高,D(La)可达5.0。在pH为2.0~2.5的硝酸体系中,恒定DTPA/HEDTA和乳酸的浓度分别为0.02 mol/L和1.0 mol/L,此时Ac^(3+)被有效掩蔽,D(Ac)的最大值仅有0.46,SF(La/Ac)值较盐酸体系的3~4可提高至5~7。此外,该非皂化P507体系也可以优先去除稀土低酸废水中的放射性Ac^(3+),其SF(Ac/La)值随乳酸浓度的增加可提高至14,这一现象能够用于实现有效控制稀土工业废水中放射性物质的目标。 展开更多
关键词 镧-锕 萃取分离 非皂化体系 P507 稀土工业
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改进和优化黑果枸杞及其制品中花青素测定的pH示差法 被引量:1
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作者 谭亮 杲秀珍 +2 位作者 王环 赵静 李玉林 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期267-278,共12页
建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质... 建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质谱法鉴别出黑果枸杞中花青素的具体化学结构,并计算出混合花青素的平均摩尔质量。通过分光光度法测得混合花青素的平均摩尔消光系数,对改进后的pH示差法进行方法学验证和花青素的含量测定。结果显示,最佳提取和检测条件如下:黑果枸杞花青素提取溶剂为盐酸-80%(体积分数)乙醇(3∶97,体积比),料液比为1∶100(g∶mL),提取温度为50℃,提取时间为30 min,缓冲溶液稀释5倍后静置平衡20 min。液相色谱-三重四级杆串联质谱法鉴别黑果枸杞中主要以矮牵牛素类花青素为主(占97.96%),黑果枸杞特有的混合花青素平均摩尔质量为912.7 g/mol,平均摩尔消光系数为29591 L/(mol·cm)。pH示差法改进后能够满足方法学验证要求,固体样品和液体样品最低检出限分别为28.2 mg/100 g、0.282 mg/100 mL。方法改进后花青素提取增长率均大于20%,静置平衡20 min后单次检测结果精密度小于0.3%。以矮牵牛素类花青素代替矢车菊素-3-O-葡萄糖苷计算花青素含量平均提高了2.41倍,能真实地反映黑果枸杞及其制品中花青素的含量。 展开更多
关键词 黑果枸杞及其制品 花青素 AOAC法 pH示差法改进 提取和检测条件优化 液相色谱-三重四级杆串联质谱法鉴别 平均摩尔质量和平均摩尔消光系数优化
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煤矸石精确产酸潜力评价方法对比研究
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作者 孙红福 阴祥诚 +3 位作者 孙朗 赵峰华 朱孟浩 范紫仪 《矿业科学学报》 CSCD 北大核心 2024年第1期13-21,共9页
为有效避免重大酸性水污染事故,需提高矿山岩石产酸潜力评价的精度。通过全面阐述矸石中常见含硫矿物的产酸潜力计算方法,采用三步连续提取法测定了多个矿石和煤矸石中产酸矿物的硫含量,对比分析了精确产酸潜力和最大产酸潜力。结果表明... 为有效避免重大酸性水污染事故,需提高矿山岩石产酸潜力评价的精度。通过全面阐述矸石中常见含硫矿物的产酸潜力计算方法,采用三步连续提取法测定了多个矿石和煤矸石中产酸矿物的硫含量,对比分析了精确产酸潜力和最大产酸潜力。结果表明:煤矸石的产酸潜力值取决于各产酸硫的质量分数和单位硫产酸值;对大部分样品,用产酸硫含量计算的产酸潜力值不同程度地低于用全硫预测的产酸潜力值;样品SC中的硫成分主要为砷黄铁矿硫,相比黄铁矿的单位硫产酸值更高,导致SC样品计算的精确产酸潜力相比全硫预测的产酸潜力更高;三步连续提取法适用于以铁和铜的硫化物为主要含硫矿物的煤矸石;当矿石中其他硫化物成分增多和空白样品混合不均匀都会对结果产生一定干扰。研究结果为准确评价矿区煤矸石精确产酸潜力提供了依据。 展开更多
关键词 产酸潜力 含硫矿物 煤矸石 三步连续提取法 酸性水预测
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多源点云优化的城市三维模型构建
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作者 鲁一慧 魏国忠 +1 位作者 宋禄楷 朱丰琪 《测绘通报》 CSCD 北大核心 2024年第S01期23-28,共6页
简易模型与传统复杂的单体模型相比,对存储、可视化、传输和后续应用技术要求低,敏感信息承载量少,且能满足大部分应用需求,具有更高的应用价值。考虑应用需求与技术现状,自然资源部将城市三维模型(L0D1.3级)纳入实景三维中国建设任务... 简易模型与传统复杂的单体模型相比,对存储、可视化、传输和后续应用技术要求低,敏感信息承载量少,且能满足大部分应用需求,具有更高的应用价值。考虑应用需求与技术现状,自然资源部将城市三维模型(L0D1.3级)纳入实景三维中国建设任务中。目前相关生产以半自动化采集为主,工程化应用存在技术流程烦琐、效率较低且对数据量限制较大等问题。本文立足山东实际,提出了一种基于多源点云优化的城市三维模型快速构建技术,在充分利用现有数据基础上有效提升了数据处理效率,大幅减少了生产成本,并在实景三维山东建设过程中得到了有效验证,具有较好的社会经济效益与推广价值。 展开更多
关键词 城市三维模型(LOD1.3级) 机载激光点云 Mesh三维模型 轮廓提取 规模化高效生产
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PRiME HLB前处理技术联合超高效液相色谱-三重四极杆质谱系统检测水产品中17种磺胺类药物残留
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作者 余海芬 徐桦 +5 位作者 吴真善 包蔚 朱晓芸 何锴 黄忠 战涛 《现代食品》 2024年第1期213-215,224,共4页
使用通过型固相萃取小柱PRi ME HLB处理水产品样品,建立了一种水产品中17种磺胺类药物的简单、快速的筛选分析方法。水产品样品经80%乙腈水溶液(含0.2%甲酸)提取,过PRi ME HLB固相萃取柱净化,浓缩后经C_(18)色谱柱梯度洗脱分离,超高效... 使用通过型固相萃取小柱PRi ME HLB处理水产品样品,建立了一种水产品中17种磺胺类药物的简单、快速的筛选分析方法。水产品样品经80%乙腈水溶液(含0.2%甲酸)提取,过PRi ME HLB固相萃取柱净化,浓缩后经C_(18)色谱柱梯度洗脱分离,超高效液相色谱-三重四极杆质谱系统进行定量分析。结果表明,17种磺胺类药物在1.0~50.0 ng·mL^(-1)线性关系良好,相关系数R^(2)>0.99;该方法检出限为2μg·kg^(-1);添加浓度为10μg·kg^(-1)时方法回收率在71.3%~118.4%,RSD值均小于20%。 展开更多
关键词 磺胺 水产品 PRiME HLB固相萃取小柱
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基于层次分析法的崂山旅游文创设计
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作者 宋美音 钱琳琳 《设计》 2024年第1期52-56,共5页
基于层次分析法,建立一种旅游文创产品设计流程,并将崂山旅游文化融入文创产品的设计中,发挥崂山当地文化特色,深入挖掘崂山旅游文化内涵,为旅游文创产品设计提供多元化设计思路。首先,从线上线下两方面调研崂山旅游文化,构建文化筛选... 基于层次分析法,建立一种旅游文创产品设计流程,并将崂山旅游文化融入文创产品的设计中,发挥崂山当地文化特色,深入挖掘崂山旅游文化内涵,为旅游文创产品设计提供多元化设计思路。首先,从线上线下两方面调研崂山旅游文化,构建文化筛选评价模型并以此为参考,筛选合适的崂山旅游文化要素,然后将筛选出的文化要素用因子提取的方法进行图案提炼,并将其运用到文创产品的设计中,最后,运用模糊综合评价法对设计出的方案进行评价。建立旅游文创设计流程,完成崂山旅游文创产品设计。在崂山旅游文创产品设计中,通过运用AHP层次分析法,初步构建满足旅游文创开发的设计需要;能够更加客观完善地选取崂山道教旅游文化元素,结合当地文旅特色完成文创产品的创作,力求传播当地文化特色,是文旅产品设计的新思路。 展开更多
关键词 AHP层次分析法 崂山旅游文化 模糊综合评价法 因子提取法 文创产品设计 文旅产品
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基于蒲剧元素的文创产品设计策略研究
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作者 樊荣 陈紫琪 李楠 《设计》 2024年第7期4-7,共4页
研究蒲剧元素在文创产品中的应用。通过对蒲剧文化的梳理,从角色行当、人物脸谱、服饰、特技表演等角度挖掘蒲剧艺术特征,提炼出适用于蒲剧文创产品设计元素。结合蒲剧文创设计策略,将动态化的戏曲表演以静态视觉设计语言表达出来,以蒲... 研究蒲剧元素在文创产品中的应用。通过对蒲剧文化的梳理,从角色行当、人物脸谱、服饰、特技表演等角度挖掘蒲剧艺术特征,提炼出适用于蒲剧文创产品设计元素。结合蒲剧文创设计策略,将动态化的戏曲表演以静态视觉设计语言表达出来,以蒲剧中生旦净丑角色形象融入品牌文创产品设计中。提高蒲剧文创的识别度和认同感,增强地方戏曲传播文化特色的效率,促进大众对传统地方戏曲的参与度,为传统戏曲的文创产品设计提供思路。 展开更多
关键词 蒲剧 戏曲文创 元素提取 文创产品 文化创意
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