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Combined Extracting Process and Activity Detection of Porcine Blood Superoxide Dismutase
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作者 王永芬 索江华 +2 位作者 李华玮 吴学军 张俊英 《Animal Husbandry and Feed Science》 CAS 2009年第3期7-10,共4页
[Objective] TO study the combined extracting process of porcine blood superoxide dismutase (SOD) and other bioactive substances and thus to provide technical basis for making full use of blood resources and large-sc... [Objective] TO study the combined extracting process of porcine blood superoxide dismutase (SOD) and other bioactive substances and thus to provide technical basis for making full use of blood resources and large-scale production of SOD. [Method] Fibronectin, immunoglobulin, and hemoglobin were isolated from porcine blood, and SOD was extracted. Trace pyrogallol self-oxidation method to determine SOD activity was modified by optimizing the volume of pyrogallol and SOD samples, reaction temperature, and buffer pH. The specific activity of SOD was determined with the optimized extraction conditions. [ Result] The improved experimental conditions of SOD activity detection were as follows: 7 pyrogallol (50 mmol/L), 3 ml Tris-HCI (50 mmol/L, pH 8.2), reactive temperature at 25(3, and 10 pl SOD sample solution. The specific activity of extracted SOD was 5 056 U/mg protein. [ Conclusion] Four kinds of bioactive substance can be isolated from porcine blood by modern biological engi- neering integration technology, and the extracted SOD has better activity. 展开更多
关键词 Porcine blood Superoxide dismutase combined extracting Activity detection
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Study on Extraction of Oolong Tea Assisted by Ultrasonic Wave and 4C Technique and Its Application
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作者 Guofeng YU Cuishu LENG +9 位作者 Keli FANG Zhiguang LIU Jianhong SUN Zengyu Wang Xuegang LI Shuai Zhang Jian LIU Xulun WEI Qiulin LIU Shoujie NIE 《Agricultural Biotechnology》 2024年第3期24-27,共4页
[Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea ext... [Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea extract in cigarettes was studied.[Results]①In the experimental range,the best sensory evaluation effect of formula oolong tea extract was obtained with extraction conditions of 70%ethanol as extraction solvent,extraction time h,extraction temperature 25℃,and ultrasonic frequency 80 kHz,and follow-up low-temperature concentration,low-temperature sedimentation and low-temperature centrifugation.②The effects of different centrifugal speeds on the quality of formula oolong tea extract were explored.The formula oolong tea extract obtained under the conditions of 3000 r/min and centrifugal time of 10 min showed the best evaluation effect with soft and delicate smoke,rich smoke fragrance,good comfort and refreshing mouthfeel.③The effective aroma components in the formula oolong tea extract were qualitatively analyzed by GC-MS.[Conclusions]This study provides high-quality raw materials and a theoretical basis for the research of independent flavor blending in cigarette industry enterprises. 展开更多
关键词 combined application of ultrasonic wave and 4C technique Orthogonal experiment Formula extraction FLAVOR
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Characterization of stereostructure by X-ray and technology of extracting in combination hydrolysis in situ of acankoreanogenin from leaves of Acanthopanax gracilistylus W.W.Smith 被引量:1
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作者 戴玲 刘向前 +1 位作者 谢霞 刘恒言 《Journal of Central South University》 SCIE EI CAS 2014年第8期3063-3070,共8页
To study the stereostructure by X-ray and the technology of extracting acankoreanogenin from the leaves of Acanthopanax graeilistylus W. W. Smith (AGS), the crystal structure was measured with a Bruker APEX-Ⅱ area-... To study the stereostructure by X-ray and the technology of extracting acankoreanogenin from the leaves of Acanthopanax graeilistylus W. W. Smith (AGS), the crystal structure was measured with a Bruker APEX-Ⅱ area-detector diffractometer instrument and the technology of extracting in combination hydrolysis in situ (ECHS) was compared with these of traditional methods. The crystal belongs to the monoclinic system, space group P2b with unit cell parameters: a=(8.3652±0.0006) nm, b=(24.721±0.002) nm, and c=(14.5587±0.0011) nm, α=90°, β=97.850 (4) °, γ=90 °, V=2982.51 nm3, Dc= 1.179 mg/m3, and the molecular number (Z) of elementary structures was 2. The comparisons show that the extraction rate of acankoreanogenin with ECHS methods is much higher than that of traditional methods. Then, central composite design-response surface methodology (CCD-RSM) was adopted for optimizing the extraction rate of ECHS methods. The optimized values of extraction parameters are as follows: for the for extraction process of acid hydrolysis are that extraction time 110.8 min, solvent-herb ratio 11.5 and acid content 5.25%; the best extraction process of basic hydrolysis are that extract time 120 min, solvent-herb ratio 8.7 and the alkali content 8.79%. Finally, the extracts were purified with decolorizing carbon after alkali solution and acid-isolation and purity of acankoreanogenin was 98.7%. 展开更多
关键词 acankoreanogenin extraction in combination hydrolysis in situ Acanthopanax gracilistylus W. W. Smith (AGS) centralcomposite design-response surface methodology
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A Clinical Analysis of 120 Cases with Traumatic Cataract Treated by Extracapsular Cataract Extraction and Posterior Chamber Intraocular Lens Implantation
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作者 汤崇凯 马赛芬 《The Journal of Biomedical Research》 CAS 1998年第1期44-46,共3页
Extracapsular cataract extraction was performed combined with posterior chamber intraocular lens implantation on 120 inpatients (122 eyes) with traumatic cataract from 1992 to 1997. The results revealed that this comb... Extracapsular cataract extraction was performed combined with posterior chamber intraocular lens implantation on 120 inpatients (122 eyes) with traumatic cataract from 1992 to 1997. The results revealed that this combined operation can make most of them get useful visual acuity, although they were often accompanied with several comlicated eye injuries. We think the most important thing is to choose suitable opertion time, the reasonable operation method and take close followup after operation. 展开更多
关键词 traumatic cataract extracapsular cataract extraction (ECCE) posterior chamber intraocular lens(PCIOL) implantation combined operation
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Mathematical Expression Extraction in Text Fields of Documents Based on HMM
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作者 Xuedong Tian Ruihan Bai +2 位作者 Fang Yang Jinyuan Bai Xinfu Li 《Journal of Computer and Communications》 2017年第14期1-13,共13页
Aiming at the problem that the mathematical expressions in unstructured text fields of documents are hard to be extracted automatically, rapidly and effectively, a method based on Hidden Markov Model (HMM) is proposed... Aiming at the problem that the mathematical expressions in unstructured text fields of documents are hard to be extracted automatically, rapidly and effectively, a method based on Hidden Markov Model (HMM) is proposed. Firstly, this method trained the HMM model through employing the symbol combination features of mathematical expressions. Then, some preprocessing works such as removing labels and filtering words were carried out. Finally, the preprocessed text was converted into an observation sequence as the input of the HMM model to determine which is the mathematical expression and extracts it. The experimental results show that the proposed method can effectively extract the mathematical expressions from the text fields of documents, and also has the relatively high accuracy rate and recall rate. 展开更多
关键词 Mathematical Expression extraction Hidden MARKOV Model TEXT FIELDS DOCUMENTS SYMBOL combination Features
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Modification of evidence theory based on feature extraction
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作者 杜峰 施文康 邓勇 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第6期667-673,共7页
Although evidence theory has been widely used in information fusion due to its effectiveness of uncertainty reasoning, the classical DS evidence theory involves counter-intuitive behaviors when high conflict informati... Although evidence theory has been widely used in information fusion due to its effectiveness of uncertainty reasoning, the classical DS evidence theory involves counter-intuitive behaviors when high conflict information exists. Many modification methods have been developed which can be classified into the following two kinds of ideas, either modifying the combination rules or modifying the evidence sources. In order to make the modification more reasonable and more effective, this paper gives a thorough analysis of some typical existing modification methods firstly, and then extracts the intrinsic feature of the evidence sources by using evidence distance theory. Based on the extracted features, two modified plans of evidence theory according to the corresponding modification ideas have been proposed. The results of numerical examples prove the good performance of the plans when combining evidence sources with high conflict information. 展开更多
关键词 evidence theory combination rule feature extraction evidence distance
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Protective effect of BlingLife®-berry extract on blue lightinduced eye damage and its mechanism
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作者 Jiaxiang Ding Chenfeng Shou Kexin Xie 《Asian Journal of Traditional Medicines》 2024年第1期1-9,共9页
This study aims to investigate the protective effects of BlingLife®-berry extract on the eyes.BlingLife®-berry extract is a mixture of high-quality natural berries,including blackcurrant,aromia,bilberry and ... This study aims to investigate the protective effects of BlingLife®-berry extract on the eyes.BlingLife®-berry extract is a mixture of high-quality natural berries,including blackcurrant,aromia,bilberry and maquiberry.The main active ingredient responsible for theeye-protective effects is anthocyanins.Anthocyanins are natural water-soluble pigments belonging to the flavonoid class,and theyhave multiple benefits,including improving vision,anti-inflammatory and antibacterial properties,and antioxidant effects.Dueto the dual benefits of anthocyanins in protecting vision and eliminating free radicals,this study explores the comprehensive eye protective effects of BlingLife®-berry extract in terms of combating blue light-induced eye damage and oxidative stress-inducedvisual fatigue.The results provide robust evidence for the in vivo effects and further technological applications of BlingLife®-berry extract. 展开更多
关键词 BlingLife®-berry extract combination anthocyanins ANTIOXIDANT protecting vision eliminating radicals
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The efficacy of a novel tomato extracts formulation on skin aging and pigmentation:A randomized,double-blind,parallel-controlled trial
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作者 Silu Zhang Shan Lu +2 位作者 Yun Wang Jiayi Ni Guoxun Xiao 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第1期13-20,共8页
Background:Oxidative stress is a significant factor in skin aging and pigmentation,which can be precipitated by various circumstances.Antioxidants and tyrosinase inhibitors,such as carotenoids,yeast extract(glutathion... Background:Oxidative stress is a significant factor in skin aging and pigmentation,which can be precipitated by various circumstances.Antioxidants and tyrosinase inhibitors,such as carotenoids,yeast extract(glutathione),sodium hyaluronate,astaxanthin,and niacin,can individually protect the skin against aging through distinct mechanisms.These mechanisms potentially enhance the skin barrier and improve signs of aging and pigmentation.However,the synergistic effects of these compounds,as found in a golden tomato extract formulation,have been scarcely explored.Objective:To evaluate the effects of an orally administered formulation on the skin aging and pigmentation.Material and Methods:In this study,a randomized,double-blind,parallel-controlled trial was conducted,utilizing the WONDERLAB?Tomato Niacinamide beverage.Out of all participants,62 volunteers completed the experiment and were included in the statistical analysis.Results:The results indicated that after eight weeks of consuming the research product,there were no significant changes in the skin indicators within the placebo group.In contrast,the treatment group receiving the sample formulation exhibited a 35.63%increase in stratum corneum hydration and a 29.39%reduction in transepidermal water loss(TEWL),suggesting enhanced skin hydration.Visual assessments revealed improvements in skin color and gloss index by 15.03%and 11.41%,respectively,in the treatment group.Furthermore,the skin gloss and individual typology angle(ITA)value increased by 18.59%and 6.36%,respectively,leading to a lighter skin tone.Significant enhancements were also observed in skin pigmentation,color uniformity,and redness.After eight weeks of intervention with the sample,blood levels of superoxide dismutase(SOD)and glutathione peroxidase(GPx)increased,while malondialdehyde(MDA)levels decreased.Conclusion:These findings confirm that continuous intake of the tomato extract formulation over eight weeks effectively improved the volunteers'skin whitening and hydration,and visibly brightened skin tone through an antioxidant mechanism. 展开更多
关键词 Skin whitening Skin aging Antioxidant Gold tomato extracts combination effect
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The optimization of ultrasonic-microwave assisted synergistic extraction of Lotus plumule extract rich in flavonoids and its hypoglycemic activity 被引量:2
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作者 Qiuzhe Li Xiaoqing Li +1 位作者 Baodong Zheng Chao Zhao 《Food Production, Processing and Nutrition》 2021年第1期263-273,共11页
Lotus(Nelumbo nucifera Gaertn),a kind of perennial aquatic plant,is widely cultivated and consumed by people in Asian countries.Lotus plumule flavonoids(LPF)have been recognized as a hypoglycemic agent.LPF was optimal... Lotus(Nelumbo nucifera Gaertn),a kind of perennial aquatic plant,is widely cultivated and consumed by people in Asian countries.Lotus plumule flavonoids(LPF)have been recognized as a hypoglycemic agent.LPF was optimally obtained using novel ultrasonic-microwave assisted synergistic extraction(UMSE)method by response surface methodology(RSM)on the basis of the results of single-factor experiments.Furthermore,the hypoglycemic activity of LPF was investigated by measuring the body weight,fasting blood glucose(FBG)level,and oral glucose tolerance test(OGTT)and analyzing the physiological indexes in streptozotocin-diabetic mice model.The optimum extraction conditions consisted of microwave power 355 W,ultrasonic power 423 W,extraction time 15 min,solid-liquid ratio 1:40,ultrasound/interval time 1/0,and ethanol concentration 70%with the maximum LPF yield of 2.62%.LPF supplementation significantly decreased the body weight,FBG,OGTT,serum total cholesterol(TC),serum total triglycerides(TG),and insulin levels,indicating the antidiabetic activity of LPF.This research verified that the UMSE technique was highly efficient to extract LPF to the maximum extent and the flavonoids from L.plumule exhibited hypoglycemic activity,which showed broad development and application prospects. 展开更多
关键词 Lotus plumule FLAVONOIDS ultrasonic-microwave assisted synergistic extraction HYPOGLYCEMIC
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Treatment of 482 Cases of Cervical Spondylopathy by Combining Point-injection and Needle-warming via Moxibustion 被引量:1
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作者 王光月 屈凤林 陈海英 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2001年第1期31-33,共3页
From January 1993 to December 1996, we treated 482 cases of cervical spondylopathy with a combined method of point-injection and needle-warming via moxibustion. Except for the cases of sympathetic nerve type and spina... From January 1993 to December 1996, we treated 482 cases of cervical spondylopathy with a combined method of point-injection and needle-warming via moxibustion. Except for the cases of sympathetic nerve type and spinal cord type, the combined method was superior to traction therapy in the control group and reported as follows.Clinical DataThe Criteria of Diagnosis and Curative Effect in TCM issued by the State Administrative Bureau of TCM and Pharmacy in 1994 was adopted for the enrollment of patients of cervical spondylopathy and the pathological typing. Only the patients who had completed the treatment and with complete records were collected for analysis. 展开更多
关键词 Acupuncture Points Acupuncture Therapy Cervical Vertebrae MOXIBUSTION Plant extracts Adult Aged Drug combinations Drugs Chinese Herbal Female Humans INJECTIONS Male Middle Aged PHENANTHROLINES Spinal Osteophytosis Vitamin B 12
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Possible Chemosensitizing and Potent Anticancer Effects of D-Fraction in Combination with Vitamin C on Three Prevalent Urologic Cancer Cells
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作者 Drew Freilich Eric Moskowitz +3 位作者 Nicholas Feuer Muhammad Choudhury John Phillips Sensuke Konno 《Journal of Cancer Therapy》 2014年第14期1402-1411,共10页
Chemotherapy is currently one of the most common therapeutic options for cancer patients despite the poor efficacy with considerable side effects. We then examined if D-fraction (DF), a bioactive mushroom extract, cou... Chemotherapy is currently one of the most common therapeutic options for cancer patients despite the poor efficacy with considerable side effects. We then examined if D-fraction (DF), a bioactive mushroom extract, could potentiate (poor) anticancer effects of those drugs?in vitro. Three urologic cancers, prostate, bladder, and kidney cancers, were tested with various chemotherapeutic drugs and their combinations with DF. Compared to individual drugs alone, combinations of drugs and DF have improved anticancer activity, resulting in the significant (P < 0.05) cell viability reduction in all three cancer cells. As vitamin C (VC) has been postulated to potentiate the bioactivity of DF, this possibility was also examined. The specific combination of DF (300 μg/ml) and VC (200 μM) indeed led to the drastic (≥90%) viability reductions in all three cancer cells. To have a better understanding of such a profound viability reduction, the effect of DF/VC combination on cell cycle was examined next. Cell cycle analysis indicated that this combination induced a G1cell cycle arrest, which was also confirmed by the down-regulation of specific cell cycle regulators (CDK2, CDK4, and cyclin D1) detected on western blots. Moreover, it was crucial to address if the DF/VC-induced viability reduction could be also linked to apoptosis. Western blot analysis revealed that anti-apoptotic bcl-2 was down-regulated while pro-apoptotic Bax was up-regulated with DF/VC combination in all cancer cells, indicating induction of apoptosis. Therefore, the DF/VC combination could ultimately induce apoptosis, accounting for the severe cell viability reduction. In conclusion, DF appears to be a promising agent with chemosensitizing effect, enhancing the efficacy of chemotherapeutic drugs, and its combination with VC exhibits a potent anticancer effect, which is far superior to any combinations of drugs and DF tested in three prevalent urologic cancer cells. 展开更多
关键词 MUSHROOM extract Chemosensitizing EFFECT ANTICANCER EFFECT combinATION Therapy UROLOGIC CANCERS
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The influence of Fe extracting as a filler of fiber concrete performance
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作者 Nawir Rasidi 《Journal of Civil Engineering and Architecture》 2009年第5期46-52,共7页
This research is showing the effect of increasing an Fe extracting from the compression strength, tension and bending moment. The variations in this experiment are the increasing of Fe extracting 0.5%, 1% and 1.5% of ... This research is showing the effect of increasing an Fe extracting from the compression strength, tension and bending moment. The variations in this experiment are the increasing of Fe extracting 0.5%, 1% and 1.5% of concrete volume. Water Cement Ratio (WCR) variation of 0.48, 0.56 and 0.60. The result of increasing 1.5% Fe extracting causes the increasing of tension strength 44.028 kN/cm2, the increasing of slit tension strength 2.226 kN/cm2, the increasing of bending moment 14.81 kN/cm2 from normal concrete. 0.48 WCR produces tension strength, slit tension strength and bending moment more than 0.56 and 0.60 WCR. The increasing of Fe extracting with the distribution variation area and the spread concrete in the tension concrete area produce 3.705 kN/cm2 bending moment higher than the spread fiber in all of concrete area. The 4 cm fiber length produces the higher bending moment than the 2 cm fiber length. The difference is equally 5.185 kN/cm2. The combination result of the examined acting varieties by continuation statistic test gives the result to get the maximum tension and split tensile. It is a concrete combination of increasing 1.5% fiber percentage, 0.48 WCR, full spreading area and the 4 cm fiber length. The maximum bending moment is the increasing of 0.5% fiber percentage, 0.48 WCR, full spreading area and the 4 cm fiber length. 展开更多
关键词 Fe extracting fiber concrete performance acting combination
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Investigatory Study of Long Term Doses of <i>Costus afer</i>, Snail Slime, and Their Combination with a Standard Pharmaceutical Drug on Blood Glucose Level of Alloxan Induced Swiss Albino Rat
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作者 Matthew Onyema Agu Barminas Jeff Tsware +2 位作者 A.Osemeahon Sunday Jude Chinedu Onwuka Hotton Joseph Anthony 《Open Journal of Medicinal Chemistry》 2018年第1期1-14,共14页
The Plant, Costus afer Ker Gawl. belongs to the family of Costaceae and has various uses where they exist. Their use in folk medicine and phytomedicine is in the treatment and management of variety of human ailment, l... The Plant, Costus afer Ker Gawl. belongs to the family of Costaceae and has various uses where they exist. Their use in folk medicine and phytomedicine is in the treatment and management of variety of human ailment, like diabetes mellitus, abdominal problems etc. The search for new antidiabetic therapies has become increasingly urgent due to the development of adverse effects and resistance by the chemically synthesized drugs on one hand and effectiveness with low cost of the plant materials on the other hand. The investigations carried out is to determine the long term effects of Costus afer leaf methanol extract, snail slime and the combined Costus afer and snail slime extracts on blood glucose levels of alloxan induced diabetic Swiss albino rats treated orally for 21 days on graded dose of (100 mg/kg and 300 mg/kg). From the determination, the snail slime showed positive effect on blood glucose lowering level but less effective when compared with similar dose of the Costus afer leaf methanol extract. The investigation indicated that there was 103 mg/dL and 87 mg/dL blood glucose reduction for the low dose of Costus afer and Snail slime respectively while the standard hypoglycemic drug (Glibenclamide, 5 mg/kg) used for comparison yielded a blood glucose level reduction of 103 mg/dL. Similarly, the high dose used in the study gave a blood glucose reduction of 99 mg/dL and 95 mg/dL for Costus afer leaf methanol extract and Snail slime respectively. The results obtained when alloxan induced rats was treated with C. afer leaf methanol extract, Snail slime extract, and combined C. afer and snail slime extracts was analysed using Statistix 8.0 American version. The result showed a dose dependent fashion and the difference obtained from the compared results was statistically significant at p 1]. Still to that, medicinal and pharmacological activities of medicinal plants are often attributed to the presence of the so called secondary plant metabolites. Hence this regenerative capacity of snail slime and the fact that diabetes is characterized by damage of the pancreatic beta cells, may give credit to the hypoglycaemic effect observed in Costus afer methanol leaf extract and snail slime for possible drug formulation for anti-diabetic remedy. Our findings may approve snail slime which is insoluble in both acid and alkaline medium, to act as a carrier of chemical and biological nanoparticles for medical and pharmaceutical use. 展开更多
关键词 Nanoparticles combined Costus afer and SNAIL SLIME extract HYPOGLYCAEMIC GLIBENCLAMIDE PHYTOMEDICINE SNAIL SLIME Costus afer Antidiabetic
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环境放射性样品中锕系核素组合分离方法研究进展
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作者 古梅 吕开 +1 位作者 熊亮萍 胡胜 《材料导报》 EI CAS CSCD 北大核心 2024年第24期76-83,共8页
环境放射性样品中锕系核素的准确分析依赖于可靠的化学分离。锕系组合分离是一种快速分离方法,具有同时分离多种核素、提高样品利用率,减少试剂用量和废物产生量等显著优势,成为锕系分析化学的研究热点。本工作综述了锕系核素分离方法... 环境放射性样品中锕系核素的准确分析依赖于可靠的化学分离。锕系组合分离是一种快速分离方法,具有同时分离多种核素、提高样品利用率,减少试剂用量和废物产生量等显著优势,成为锕系分析化学的研究热点。本工作综述了锕系核素分离方法及各方法的组合使用,以及自动化分离在锕系组合分离中的应用现状,并重点介绍了基于萃取色谱法的锕系组合分离研究进展。在此基础上,指出建立锕系核素组合分离方法面临的问题,并对该领域的发展趋势进行了展望。 展开更多
关键词 锕系核素 组合分离流程 萃取色谱
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曲线拟合与分段函数组合法在瓦斯抽采量预测中的研究与应用
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作者 程磊 王鑫 张清田 《煤炭技术》 CAS 2024年第1期185-189,共5页
为减少矿井煤与瓦斯突出、瓦斯爆炸等事故的发生,将井下瓦斯及时抽出是必要的,因此对瓦斯抽采量进行准确地预测愈发重要。在神经网络法、多元线性回归法等预测方法的基础上,根据瓦斯抽采量在时间效应下变化波动大的特性,提出了曲线拟合... 为减少矿井煤与瓦斯突出、瓦斯爆炸等事故的发生,将井下瓦斯及时抽出是必要的,因此对瓦斯抽采量进行准确地预测愈发重要。在神经网络法、多元线性回归法等预测方法的基础上,根据瓦斯抽采量在时间效应下变化波动大的特性,提出了曲线拟合与分段函数组合法。此方法以瓦斯抽采量衰减为界将瓦斯抽采分为前、后2个阶段,根据实测数据作抽采纯量随时间变化曲线并对变化曲线进行拟合,根据拟合曲线列出预测瓦斯抽采量的计算公式,用于对抽采量进行预测。分别对九里山矿、古汉山矿进行后段抽采量预测与实际的比较,其中九里山矿得到后段预测值的最小相对误差为0.63%,最大相对误差为2.34%,古汉山矿得到后段预测值的最小相对误差为0.09%,最大相对误差为3.23%。表明曲线拟合与分段函数组合法对井下瓦斯抽采量预测是可行的,对井下瓦斯治理具有重要的意义。 展开更多
关键词 瓦斯抽采 抽采量预测 曲线拟合与分段函数组合法 时间效应 瓦斯治理
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基于组合相似度动态聚类和词熵的网络话题在线检测
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作者 郭慧 王亚楠 +2 位作者 王欣艳 魏艺泽 王养廷 《情报杂志》 CSSCI 北大核心 2024年第5期159-166,共8页
[研究目的]为实现网络热点话题的在线检测,提升增量式聚类算法的聚类效果,提出了基于组合相似度的动态聚类算法,同时通过计算词熵实现主题词提取和演化跟踪。[研究方法]通过CIFG-BiLSTM-CRF模型实现文本的命名实体识别,计算文本与话题... [研究目的]为实现网络热点话题的在线检测,提升增量式聚类算法的聚类效果,提出了基于组合相似度的动态聚类算法,同时通过计算词熵实现主题词提取和演化跟踪。[研究方法]通过CIFG-BiLSTM-CRF模型实现文本的命名实体识别,计算文本与话题的实体相似度,再取文本词向量与话题中心余弦相似度的最大值作为词向量相似度,二者结合判断文本所属话题。在聚类过程中利用时间窗口策略实现话题中心和成员文本的动态更新。同时,计算文本词熵,生成话题的词熵和列表,实现话题主题词提取和演化跟踪。实验以新冠疫情新闻为数据实现话题在线检测,并展示了话题主题词的演化和跟踪过程。[研究结论]实验表明,与传统相似度计算方法相比,组合相似度能够获得更好的聚类效果,聚类过程中提取出的话题主题词也正确地反映了原始数据的热点话题内容。 展开更多
关键词 网络话题 在线话题检测 增量式聚类 主题词提取 组合相似度 动态聚类算法 词熵
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试验环境水下声信号的特征提取方法
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作者 王红滨 王永乐 +1 位作者 何鸣 薛垚 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第3期489-495,共7页
水下试验环境参数的反演是水声学研究领域的重要内容。而当前研究的关键是通过对水下声信号做特征提取从而获取参数信息。针对特征提取较难、模型很难拟合等问题。本文提出了一种试验环境水下声信号的特征提取方法。将水下声信号同时用... 水下试验环境参数的反演是水声学研究领域的重要内容。而当前研究的关键是通过对水下声信号做特征提取从而获取参数信息。针对特征提取较难、模型很难拟合等问题。本文提出了一种试验环境水下声信号的特征提取方法。将水下声信号同时用梅尔频谱倒谱系数及线性预测系数处理,两者运用特征加权组合方法得到新的特征矩阵;再应用映射插值算法对特征矩阵进行处理,获得适应神经网络输入的三通道矩阵。本文选取的网络模型为残差神经网络。利用实验室所录制的对河口水库数据集测试表明,本文提出的特征提取方法普遍优于仅利用梅尔频谱倒谱系数或线性预测系数的特征处理方法。利用单频矩形脉冲信号对环境进行深度5分类,准确率平均提升2%。利用线性调频信号对环境进行深度5分类,准确率平均提升2.03%。本文提出的特征提取方法对线性调频信号在深度分类任务下处理的结果要优于单频矩形脉冲信号处理的结果。 展开更多
关键词 环境反演 特征提取 梅尔频谱倒谱系数 线性预测系数 特征加权组合方法 残差神经网络 神经网络 水下声信号
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烟草薄片废水中烟碱提取方法研究
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作者 韩晓芳 连祎璘 +4 位作者 肖汝侬 姜琦 艾冬黎 董涵玉 邓维冰 《绿色科技》 2024年第2期147-150,共4页
为研究Ca-Mg-Al组合混凝剂处理并富集烟草薄片废水中烟碱至固相污泥过程、提取固相污泥中的烟碱的工艺流程,通过正交试验设计和碱液浸提的方式,再采用溶剂萃取污泥浸提液中的烟碱,最后用HPLC测定污泥中烟碱含量。并对萃取剂种类、萃取... 为研究Ca-Mg-Al组合混凝剂处理并富集烟草薄片废水中烟碱至固相污泥过程、提取固相污泥中的烟碱的工艺流程,通过正交试验设计和碱液浸提的方式,再采用溶剂萃取污泥浸提液中的烟碱,最后用HPLC测定污泥中烟碱含量。并对萃取剂种类、萃取剂用量、萃取次数分别进行了单因素考察。结果表明:pH值为10.0,Ca(OH)_(2)、MgSO_(4)·7H_(2)O、Al_(2)(SO_(4))_(3)·18H_(2)O的摩尔比为12∶3∶4,组合混凝剂投加量为5.0 g/L,该条件下COD去除率达到62%,废水烟碱富集率最高可达到58.4%。最终,处理得到的污泥中烟碱含量为1.05%,具有一定提取回收价值。 展开更多
关键词 烟碱 烟草废水 Ca-Mg-Al组合混凝剂 萃取 浸提
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联合预处理提取半纤维素的研究进展 被引量:3
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作者 唐德容 陈天影 +2 位作者 李勉 杨武龙 唐艳军 《中国造纸学报》 CAS CSCD 北大核心 2024年第1期137-145,共9页
半纤维素含量丰富,应用前景广阔。但半纤维素结构复杂多样,实现其高值化利用是一个长期存在的挑战。采用单一物理法、化学法或生物法预处理提取半纤维素时,在能耗、成本、效果等方面均存在一定局限性。联合预处理可结合各种预处理方法... 半纤维素含量丰富,应用前景广阔。但半纤维素结构复杂多样,实现其高值化利用是一个长期存在的挑战。采用单一物理法、化学法或生物法预处理提取半纤维素时,在能耗、成本、效果等方面均存在一定局限性。联合预处理可结合各种预处理方法的优势,降低单一预处理的局限性,已成为目前半纤维素提取的研究热点。本文综述了木质纤维中半纤维素的联合预处理提取工艺,如超声辅助、微波辅助、酸/水热处理和碱/水热处理等,并简要介绍了各种预处理方法的优缺点,以期为半纤维素的提取及应用提供理论指导。 展开更多
关键词 联合预处理 半纤维素 提取 高值化利用
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中心组合设计-响应面法优选当归-川芎饮片苯酞、酚酸类成分提取工艺 被引量:2
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作者 苏秦 包强 +3 位作者 李喜香 王雪梅 殷润良 王建良 《中国中医药信息杂志》 CAS CSCD 2024年第4期146-152,共7页
目的优选当归-川芎饮片苯酞、酚酸类成分最佳提取工艺。方法在单因素试验基础上,采用中心组合设计-响应面法,以提取时间、乙醇浓度、乙醇用量为影响因素,洋川芎内酯I、洋川芎内酯A、藁本内酯含量及浸膏得率的总评归一值为评价指标,优选... 目的优选当归-川芎饮片苯酞、酚酸类成分最佳提取工艺。方法在单因素试验基础上,采用中心组合设计-响应面法,以提取时间、乙醇浓度、乙醇用量为影响因素,洋川芎内酯I、洋川芎内酯A、藁本内酯含量及浸膏得率的总评归一值为评价指标,优选当归-川芎饮片苯酞类成分提取工艺;以绿原酸、咖啡酸、阿魏酸含量及浸膏得率的总评归一值为评价指标,优选当归-川芎饮片酚酸类成分提取工艺。结果苯酞类成分最佳提取工艺:加7倍量90%乙醇,每次提取130 min,提取2次;酚酸类成分最佳提取工艺:加7.5倍量65%乙醇,每次提取120 min,提取2次。结论优选的当归-川芎饮片苯酞、酚酸类成分提取工艺稳定、可行,可为后续研究提供依据。 展开更多
关键词 当归-川芎饮片 苯酞类成分 酚酸类成分 中心组合设计-响应面法 提取工艺
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