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Zinc extraction from sewage sludge with [S,S]-EDDS 被引量:1
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作者 张丽华 张华 《Journal of Central South University》 SCIE EI CAS 2012年第12期3546-3550,共5页
An environmentally friendly biodegradable chelant,[S,S]-ethylenediaminedisuccinic acid(EDDS),was used to separate heavy metals from sewage sludge based on chemical extraction technology.The extraction of zinc from sew... An environmentally friendly biodegradable chelant,[S,S]-ethylenediaminedisuccinic acid(EDDS),was used to separate heavy metals from sewage sludge based on chemical extraction technology.The extraction of zinc from sewage sludge with an aqueous solution of EDDS was studied under various conditions.It is found that the extraction efficiency of zinc using EDDS is equivalent to that using ethylenediaminetetraacetic acid(EDTA)at the molar ratio of chelant to total heavy metals of 1:1 over pH range of 5-9.EDDS is capable of extracting zinc from the sludge.The extraction efficiency is improved obviously and reaches a higher value within pH range from 3 to 10.The extraction efficiency maintains at about 65% when pH≥4.5 and the ratio of 10:1.By comparing the species contents of the zinc in sewage sludge before and after the extraction,it is found that the extracted zinc mainly comes from the acid soluble,reducible and oxidizable fractions. 展开更多
关键词 ZINC [s s]-ethylenediaminedisuccinic acid extraction sewage sludge chelant biodegradablility
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Anti-inflammation Activities of Essential Oil and Anti-microbial Activities Of Ethanol Extraction from China's Rosemary 被引量:1
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作者 Jingbo ZHOU Ruqiang HUANG +1 位作者 Jihong HUANG Junwei FENG 《Agricultural Science & Technology》 CAS 2015年第5期1034-1037,1047,共5页
Rosemary(Rosmarius officinalis L.), an endemic plant species in south region of China, is traditionally used as a spice. In this research, the anti-inflammatory activities of essential oil and the antibacterial activi... Rosemary(Rosmarius officinalis L.), an endemic plant species in south region of China, is traditionally used as a spice. In this research, the anti-inflammatory activities of essential oil and the antibacterial activities of ethanol extraction were determined, respectively. Results showed that based on the GC-MS analysis there were 35 kinds of active ingredients in the essential oil in totally, mainly including D-limonene(24.158 ml/L), α-Pinene(23.325 ml/L), Camphor(9.855 ml/L),Camphene(7.076 ml/L), Verbenone(6.685 ml/L), Borneol(5.580 ml/L), etc. The LCUV determination indicated that the main components in the ethanol extractionwere rosmarinic acid(3 910 mg/kg) and carnosic acid(2 970 mg/kg). By mice peritoneal macrophage phagocytosis of chicken erythrocytes experiment, the essential oil of rosemary was shown having a significant role in anti-inflammation. And the ethanol extraction had broad-spectrum antibacterial effects, but had no effect on mold by the agar diffusion method of 8 bacteria. As a result, both rosemary essential oil and ethanol extraction had good potential medicinal values. 展开更多
关键词 China's rosemary Essential oil extraction Anti-inflammation activity Anti-microbial activity
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Content Feature Extraction-based Hybrid Recommendation for Mobile Application Services 被引量:1
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作者 Chao Ma YinggangSun +3 位作者 Zhenguo Yang Hai Huang Dongyang Zhan Jiaxing Qu 《Computers, Materials & Continua》 SCIE EI 2022年第6期6201-6217,共17页
The number of mobile application services is showing an explosive growth trend,which makes it difficult for users to determine which ones are of interest.Especially,the new mobile application services are emerge conti... The number of mobile application services is showing an explosive growth trend,which makes it difficult for users to determine which ones are of interest.Especially,the new mobile application services are emerge continuously,most of them have not be rated when they need to be recommended to users.This is the typical problem of cold start in the field of collaborative filtering recommendation.This problem may makes it difficult for users to locate and acquire the services that they actually want,and the accuracy and novelty of service recommendations are also difficult to satisfy users.To solve this problem,a hybrid recommendation method for mobile application services based on content feature extraction is proposed in this paper.First,the proposed method in this paper extracts service content features through Natural Language Processing technologies such as word segmentation,part-of-speech tagging,and dependency parsing.It improves the accuracy of describing service attributes and the rationality of the method of calculating service similarity.Then,a language representation model called Bidirectional Encoder Representation from Transformers(BERT)is used to vectorize the content feature text,and an improved weighted word mover’s distance algorithm based on Term Frequency-Inverse Document Frequency(TFIDF-WMD)is used to calculate the similarity of mobile application services.Finally,the recommendation process is completed by combining the item-based collaborative filtering recommendation algorithm.The experimental results show that by using the proposed hybrid recommendation method presented in this paper,the cold start problem is alleviated to a certain extent,and the accuracy of the recommendation result has been significantly improved. 展开更多
关键词 service recommendation cold start feature extraction natural language processing word mover’s distance
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Performance comparison of different microbial DNA extraction methods on bird feces 被引量:1
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作者 Xian Hou Shengkai Pan +2 位作者 Zhenzhen Lin Jiliang Xu Xiangjiang Zhan 《Avian Research》 CSCD 2021年第2期247-254,共8页
Background:As an important player during food digestion,gut microbiota has attracted much attention in diet adaptation studies in birds.Microbiota extracted from feces has been widely used as a proxy for gut microbiot... Background:As an important player during food digestion,gut microbiota has attracted much attention in diet adaptation studies in birds.Microbiota extracted from feces has been widely used as a proxy for gut microbiota.Although several methods have been developed for microbial DNA extraction,their performances in the bird feces have not been systematacially evaluated yet.Methods:In this study,we applied three DNA extraction methods(Qiagen,MoBio and Bead)to extract DNA from feces of three avian dietary guilds(granivore,omnivore and carnivore),sequenced V4 region of 16S rRNA gene for each extract and evaluated the performances of DNA yield,DNA integrity,microbial composition,cell lysis capacity and alpha diversity for the three methods on each dietary guild.Results:Bead method was the best on the performance of both DNA yield and DNA integrity regardless of dietary guild.In granivore,microbial relative abundance at both species and phylum levels,alpha diversity and cell lysis capacity were comparable among all methods.In omnivore,Qiagen had the best performance on alpha diversity,fol-lowed by Bead and MoBio.There were small variations on microbial relative abundance at both species and phylum levels among different extraction methods.MoBio exhibited the best performance on cell lysis capacity.In carnivore,considerable variations were found on microbial relative abundance at both species and phylum levels.Qiagen had the best performance on alpha diversity,followed by MoBio and Bead.MoBio had the highest cell lysis capacity.Conclusions:DNA yield and integrity have no obvious impact on microbial composition,alpha diversity or cell lysis capacity.The microbiota results(e.g.,microbial composition,cell lysis capacity,alpha diversity)obtained from differ-ent methods are comparable in granivorous avian species but not in omnivorous or carnivorous birds.Either method could be used in granivore microbiota studies.For omnivores and carnivores,we recommend Qiagen method when the research purpose is microbial diversity and MoBio when gram-positive bacteria is the research target. 展开更多
关键词 16s rRNA Alpha diversity AVIAN Dietary guild FECEs DNA extraction method Microbial relative abundance
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Melt extraction and mineralization: A case study from the Shuangjianzishan supergiant Ag-Pb-Zn deposit(208 Mt), Inner Mongolia, NE China 被引量:1
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作者 Meng Dai Guang-sheng Yan +3 位作者 Yong-sheng Li Wen-bin Jia Fan-yu Qi Xing Ju 《China Geology》 CAS CSCD 2023年第4期623-645,I0001-I0003,共26页
The supergiant Shuangjianzishan(SJZ) Ag-Pb-Zn deposit is in the southern segment of the Great Hinggan Range(SGHR), northeast China. Previous studies suggest the ore-forming material and fluid originated from the magma... The supergiant Shuangjianzishan(SJZ) Ag-Pb-Zn deposit is in the southern segment of the Great Hinggan Range(SGHR), northeast China. Previous studies suggest the ore-forming material and fluid originated from the magmatic system, and the mineralization age was consistent with the diagenetic age. However,the relationship between granitic magmatism and mineralization is still unclear in the SJZ. In this study, CH-O-He-Ar and in-situ S-Pb isotope analyses were conducted to determine the sources of ore-forming fluids and metals, which were combined with geochemistry data of SJZ granitoids from previous studies to constrain the relationship between the magmatism and the mineralization. The C-H-O-He-Ar-S-Pb isotopic compositions suggested the SJZ ore-forming material and fluids were derived from a magmatic source, which has mixed a small amount of mantle-derived materials. In addition, the disseminated sulfide from the syenogranite has comparable S-Pb isotopic composition with the sulfide minerals from ore veins,suggesting that the generation of the SJZ ore-forming fluids has a close relationship with the syenogranite magmatism. Combining with the geochemical characters of the syenogranite, the authors proposed that the mantle-derived fingerprint of the SJZ ore-forming fluid might be caused by the parent magma of the syenogranite, which was derived from partial melting of the juvenile lower crust, and underwent the residual melts segregated from a crystal mush in the shallow magma reservoir. The extraction of the syenogranite parent magma further concentrated the fertilized fluids, which was crucial to mineralization of the SJZ Ag-Pb-Zn deposit. 展开更多
关键词 Ag-Pb-Zn deposit D-O-C-He-Ar isotope In-situ s and Pb isotope analysis Melt extraction Ore-forming fluid syenogranite Metallogenic belt Mineral exploration engineering southern Great Hinggan Range
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A feasible and effective solution-processed PCBM electron extraction layer enabling the high VOC and efficient Cu_(2)ZnSn(S, Se)_(4) devices 被引量:1
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作者 Licheng Lou Yuancai Gong +10 位作者 Jiazheng Zhou Jinlin Wang Xiao Xu Kang Yin Biwen Duan Huijue Wu Jiangjian Shi Yanhong Luo Dongmei Li Hao Xin Qingbo Meng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期154-161,I0005,共9页
Photo-generated carrier recombination loss at the CZTSSe/Cd S front interface is a key issue to the opencircuit voltage(V_(OC)) deficit of Cu_(2)ZnSnS_(x)Se_(4-x)(CZTSSe) solar cells. Here, by the aid of an easy-handl... Photo-generated carrier recombination loss at the CZTSSe/Cd S front interface is a key issue to the opencircuit voltage(V_(OC)) deficit of Cu_(2)ZnSnS_(x)Se_(4-x)(CZTSSe) solar cells. Here, by the aid of an easy-handling spin-coating method, a thin PCBM([6,6]-phenyl-C61-butyric acid methyl ester) layer as an electron extraction layer has been introduced on the top of CdS buffer layer to modify CZTSSe/CdS/ZnO-ITO(In_(2)O_(3):Sn) interfacial properties. Based on Sn^(4+)/DMSO(dimethyl sulfoxide) solution system, a totalarea efficiency of 12.87% with a VOC of 529 m V has been achieved. A comprehensive investigation on the influence of PCBM layer on carrier extraction, transportation and recombination processes has been carried out. It is found that the PCBM layer can smooth over the Cd S film roughness, thus beneficial for a dense and flat window layer. Furthermore, this CZTSSe/Cd S/PCBM heterostructure can accelerate carrier separation and extraction and block holes from the front interface as well, which is mainly ascribed to the downward band bending of the absorber and a widened space charge region. Our work provides a feasible way to improve the front interfacial property and the cell performance of CZTSSe solar cells by the aid of organic interfacial materials. 展开更多
关键词 Cu_(2)Znsn(s se)_(4)solar cells PCBM Interfacial property Electron extraction layer Band bending
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An Impact of Hydrostatic Extraction Scheme on BMRC's Global Spectral Model 被引量:1
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作者 盛华 William Bourke Terry Hart 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期269-278,共10页
There are two important features in geophysical fluid dynamics. One is that the atmospheric and oceanic equations of motion include the Coriolis force; another is that they describe a stratified fluid. The hydrostatic... There are two important features in geophysical fluid dynamics. One is that the atmospheric and oceanic equations of motion include the Coriolis force; another is that they describe a stratified fluid. The hydrostatic extraction scheme, or standard stratification approximation, posed by Zeng (1979), reflects the second aspect of geophysical fluid dynamics. There exist two major advantages in this scheme; accurate computation of the pressure gradient force can be obtained over steep mountain slopes, and the accumulation error in vertical finite differencing can be reduced, especially near the tropopause.Chen et al (1987) introduced the hydrostatic extraction scheme into a global spectral model, which attained preliminary success at low resolution. Zhang and Sheng et al (1990) developed and improved the hydrostatic extraction scheme in a global spectral model, in which C0, the parameter that represents the stratification of the reference atmosphere, changes not only with height, but also with latitude. The scheme has been incorporated BMRC's global spectral model (IAPB). Four 5-day forecasts have been performed to test the IAPB with the hydrostatic extraction scheme. Objective verifications demonstrate a positive effect of the hydrostatic extration scheme on BMRC's model, particularly at upper levels, over the tropics and the Antartic region. 展开更多
关键词 An Impact of Hydrostatic extraction scheme on BMRC’s Global spectral Model
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Effects of a Cocktail Supplement of Ginkgo Biloba and Acai Extract on Cognitive Symptoms of Parkinson’s Disease
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作者 Yulia Dubrovensky 《Advances in Parkinson's Disease》 CAS 2024年第3期57-72,共16页
Parkinson’s Disease (PD) is a neurodegenerative disorder characterized by motor and non-motor symptoms, including cognitive impairment. Current treatments often involve synthetic drugs with significant side effects a... Parkinson’s Disease (PD) is a neurodegenerative disorder characterized by motor and non-motor symptoms, including cognitive impairment. Current treatments often involve synthetic drugs with significant side effects and potential for dependency. This study investigates the effects of a natural supplement combination of Ginkgo Biloba and Acai Extract on cognitive symptoms in a 77-year-old male with PD. The participant underwent a three-month supplementation regimen, with cognitive function assessed using the Montreal Cognitive Assessment (MoCA) test before and after the intervention. The results indicated an improvement in cognitive scores, suggesting that the combination of Ginkgo Biloba and Acai Extract may offer a promising alternative or adjunct to conventional PD treatments. This study highlights the potential of natural supplements in managing PD symptoms and calls for further research with larger sample sizes to confirm these findings. Human data was performed in accordance with the Declaration of Helsinki by the Roxbury District IRB Board (IRB Number: IRB00011767). 展开更多
关键词 Parkinson’s Disease (PD) Cognitive Function Ginkgo Biloba Acai extract Neurodegenerative Disorders Natural supplements Cognitive symptoms Montreal Cognitive Assessment (MoCA) Dopaminergic Neurons Antioxidants Neuroprotection Non-Motor symptoms Oxidative stress POLYPHENOLs
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A Semi-automatic Method Based on Statistic for Mandarin Semantic Structures Extraction in Specific Domains 被引量:1
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作者 熊英 朱杰 孙静 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期25-29,共5页
This paper proposed a new method of semi-automatic extraction for semantic structures from unlabelled corpora in specific domains. The approach is statistical in nature. The extracted structures can be used for shallo... This paper proposed a new method of semi-automatic extraction for semantic structures from unlabelled corpora in specific domains. The approach is statistical in nature. The extracted structures can be used for shallow parsing and semantic labeling. By iteratively extracting new words and clustering words, we get an inital semantic lexicon that groups words of the same semantic meaning together as a class. After that, a bootstrapping algorithm is adopted to extract semantic structures. Then the semantic structures are used to extract new 展开更多
关键词 and augment the semantic lexicon. The resultant semantic structures are interpreted by persons and are amenable to hand-editing for refinement. In this experiment the semi-automatically extracted structures s sA provide recall rate of 84.
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Curcuma′s extraction attenuates propranolol-induced psoriasis like in mice by inhibition of keratin,proliferating cell nuclear antigen and Toll-like receptor expression
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作者 LI Jin-qi ZHANG Shu-han +3 位作者 TONG Rong-sheng HE Dan ZHONG Zhen-dong SHE Shu-ya 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2016年第10期1039-1039,共1页
OBJECTIVE Recently,some reports show that curcuma has a good curative effect on the treatment of psoriasis;while curcuma has many components,so the present study was designed to investigate the effective parts of curc... OBJECTIVE Recently,some reports show that curcuma has a good curative effect on the treatment of psoriasis;while curcuma has many components,so the present study was designed to investigate the effective parts of curcuma on treatment of psoriasis,in addition,we will explore the mechanisms of curcuma therapeutic effect.METHODS First,we observed that curcuma′s extractions effect on mitosis of mouse vaginal epithelial cells;then psoriasis like was induced by wiping imiquimod in the surface of the binaural dorsal skin of the animal,the score of skin damage was measured on days 7 and 14;in order to explore the mechanisms of curcuma’s extractions on psoriasis,immune factors expression(CK14,CK16,CK17,PCNA,TLR-2,TLR-4,TLR-9)was determined in propranolol induced psoriasis like.RESULTS Curcuma′s extraction prohibited the mitosis of mouse vaginal epithelial cells;curcuma’s extractions produced a significant and dose dependent inhibition of psoriasis during the entire duration of the study in imiquimod induced psoriasis like;and the expression of immune factors(CK14,CK16,CK17,PCNA,TLR-2,TLR-4,TLR-9)was also found to be less in the curcuma′s extraction treated group as compared to control.CONCLUSION We believe that the curative effectof curcuma’sextraction may due to its inhibition effect on the expression of immune factors.Our results contribute towards validation of curcuma in the treatment of psoriasis and other joint disorders. 展开更多
关键词 PsORIAsIs curcuma′s extract ionlmmune factors
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Extraction of Partial Discharge Acoustic Signal by Wavelet Transform with Teager′s Energy Operator
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作者 杜伯学 欧阳明鉴 +1 位作者 武媛 魏国忠 《Transactions of Tianjin University》 EI CAS 2005年第4期289-294,共6页
To develop a measurement system for monitoring partial discharge (PD) without the effect of external interferences,an algorithm of PD signal extraction based on wavelet transform with Teager's energy operators was ... To develop a measurement system for monitoring partial discharge (PD) without the effect of external interferences,an algorithm of PD signal extraction based on wavelet transform with Teager's energy operators was presented. Acoustic signal generated by PD was selected to remove excessive interfering signals and electromagnetic interferences. Acoustic signals were collected and decomposed into I0 levels by wavelet transform into approximation and detail components. “Daubechies 25” was proved to be the most suitable mother wavelet for the extraction of PD acoustic signals. Compared with conventional wavelet denoising method, Teager's energy operators were adopted to the PD signal reconstruction and the signal to noise ratio was in creased by 20%-25% inthe experiment,without lost in energy and pulse amplitude. 展开更多
关键词 partial discharge extraction acoustic signal wavelet transform Teager's energy opera- tors DENOIsE
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EXTRACTION OF CHARACTERISTIC ROOTS ON BESSEL-NEUMANN’S MIXED EQUATIONS
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作者 杨文熊 顾尔祚 朱敏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第8期751-758,共8页
This paper discusses the problem of the extraction of characteristic roots on Bessel-Neumann's mixed equations. It gives the expressions and the evaluation of the minimum root. The advantage of the method has no u... This paper discusses the problem of the extraction of characteristic roots on Bessel-Neumann's mixed equations. It gives the expressions and the evaluation of the minimum root. The advantage of the method has no use for the table of the multi-figure number Bessel function and it does not need computer but can calculate all the characteristic roots The precision of these roots is still high. 展开更多
关键词 extraction OF CHARACTERIsTIC ROOTs ON BEssEL-NEUMANN s MIXED EQUATIONs
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Breakthrough in the China's Separation Technology for Extraction of Rare Earth Elements
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作者 HAO Ziguo FEI Hongcai +1 位作者 LIU Lian Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1743-1744,共2页
Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extracti... Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extraction & Equipment Co. Ltd., Baotou REE Research Institute, and Baotou Steel & REE Group Hi-Tech Co. Ltd (Inner Mongolia), has successfully solved the problem using a centrifugal extractor and advanced techniques to achieve a key breakthrough. 展开更多
关键词 LINE Breakthrough in the China’s separation Technology for extraction of Rare Earth Elements REE
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Detection of Parkinson’s Disease with Multiple Feature Extraction Models and Darknet CNN Classification
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作者 G.Prema Arokia Mary N.Suganthi 《Computer Systems Science & Engineering》 SCIE EI 2022年第10期333-345,共13页
Parkinson’s disease(PD)is a neurodegenerative disease in the central nervous system.Recently,more researches have been conducted in the determination of PD prediction which is really a challenging task.Due to the dis... Parkinson’s disease(PD)is a neurodegenerative disease in the central nervous system.Recently,more researches have been conducted in the determination of PD prediction which is really a challenging task.Due to the disorders in the central nervous system,the syndromes like off sleep,speech disorders,olfactory and autonomic dysfunction,sensory disorder symptoms will occur.The earliest diagnosing of PD is very challenging among the doctors community.There are techniques that are available in order to predict PD using symptoms and disorder measurement.It helps to save a million lives of future by early prediction.In this article,the early diagnosing of PD using machine learning techniques with feature selection is carried out.In the first stage,the data preprocessing is used for the preparation of Parkinson’s disease data.In the second stage,MFEA is used for extracting features.In the third stage,the feature selection is performed using multiple feature input with a principal component analysis(PCA)algorithm.Finally,a Darknet Convolutional Neural Network(DNetCNN)is used to classify the PD patients.The main advantage of using PCA-DNetCNN is that,it provides the best classification in the image dataset using YOLO.In addition to that,the results of various existing methods are compared and the proposed DNetCNN proves better accuracy,performance in detecting the PD at the initial stages.DNetCNN achieves 97.5%of accuracy in detecting PD as early.Besides,the other performance metrics are compared in the result evaluation and it is proved that the proposed model outperforms all the other existing models. 展开更多
关键词 Parkinson’s disease multi-variant feature extraction DarkNet CNN principle component analysis feature selection machine learning deep learning
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Ethanol Extraction of Hyoscyamus niger and Hypericum calycinum Evaluated for Acaricidal Activity against Tetranychus urticae Koch (Acari: Tetranychidae)
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作者 Pervin Erdogan Errol Hassan +1 位作者 Betul Sever Yilmaz Gulcin Saltan 《Journal of Food Science and Engineering》 2018年第1期46-54,共9页
Hyoscyamus niger L. (Solanaceae) and Hypericum calycinum L. (Hypericaceae) were collected from two provinces Bursa and Ankara in Turkey during flowering stages. Extracts obtained from H. niger and H. calycinum wer... Hyoscyamus niger L. (Solanaceae) and Hypericum calycinum L. (Hypericaceae) were collected from two provinces Bursa and Ankara in Turkey during flowering stages. Extracts obtained from H. niger and H. calycinum were tested against two-spotted mite as an acaricidal pesticide. Bioassay experiments were carried out under laboratory conditions using two different methods namely, leaf disc dipping and direct leaf spraying. Two-spotted mite was reared in insectary using Phaseolus vulgaris L. (Fabaceae). In the leaf dipping method, H. niger extract resulted in an effective adjusted mortality for larvae of 87.13% and for adults of 81.66%. For H. calycinum the adjusted mortality for larvae and adults was 77.77% and 85.97% respectively at the highest concentration. In larval stage, LCs0 values were 5.47 w/v and 3.32 w/v dipping and spraying method respectively. In addition, adult stage, it was determined that LCs0 values were 1.17 w/v and 3.56 w/v in both methods. For leaf spraying method. H. niger resulted in an adjusted showed an effect against larvae and adults mortality rate was 95% and 91% respectively. However, H. calycinum mortality percentage was 80% and 87% at 12% concentration, with LC50 values of 9.62 w/v and 2.13 w/v in dipping method. In this research apart from mortality effects on egg, reproduction was also investigated. Each concentration showed that treated females laid less eggs compared to the untreated females. 展开更多
关键词 Two-spotted spider mite henbane st-John's Wort extract acaricidal effect.
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Analytical and Numerical Model Confrontation for Transfer Impedance Extraction in Three-Dimensional Radio Frequency Circuits
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作者 Olivier Valorge Fengyuan Sun +3 位作者 Jean-Etienne Lorival Mohamed Abouelatta-Ebrahim Francis Calmon Christian Gontrand 《Circuits and Systems》 2012年第2期126-135,共10页
3D chip stacking is considered known to overcome conventional 2D-IC issues, using through silicon vias to ensure vertical signal transmission. From any point source, embedded or not, we calculate the impedance spread ... 3D chip stacking is considered known to overcome conventional 2D-IC issues, using through silicon vias to ensure vertical signal transmission. From any point source, embedded or not, we calculate the impedance spread out;our ultimate goal will to study substrate noise via impedance field method. For this, our approach is twofold: a compact Green function or a Transmission Line Model over a multi-layered substrate is derived by solving Poisson’s equation analytically. The Discrete Cosine Transform (DCT) and its variations are used for rapid evaluation. Using this technique, the substrate coupling and loss in IC’s can be analyzed. We implement our algorithm in MATLAB;it permits to extract impedances between any pair of embedded contacts. Comparisons are performed using finite element methods. 展开更多
关键词 Through silicon Via (TsV) Green’s Function Transmission Line Model Radio Frequency (RF) Transfer IMPEDANCE extraction
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Reliability Evaluation on Weak Signal Extraction for Airgun Source Surveys
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作者 Wu Anxu Ye Beng 《Earthquake Research in China》 CSCD 2018年第2期265-279,共15页
Based on the data synthesis simulation and the actual processing of the airgun seismic source signal,three quantitative indicators of signal-to-noise ratio,waveform correlation coefficient and phase offset,are superim... Based on the data synthesis simulation and the actual processing of the airgun seismic source signal,three quantitative indicators of signal-to-noise ratio,waveform correlation coefficient and phase offset,are superimposed. We systematically evaluate the functions of the following three stack methods including linearity,phase weighting and S-transform in the extraction of weak signals under strong background noise and quantitatively estimate the reliability of the stack results. Through the comprehensive discussion of the above three methods of stack results,the preliminary comparative analysis believes that the linear stack signal-to-noise ratio is low,but the waveform distortion is minimal; the phase-weighted superimposed signal-to-noise ratio is high and the phase offset is small,but the results of the waveform quality and linear stack are larger than the deviation; the S-transform stack has a relatively higher signal-to-noise ratio and a small loss of waveform amplitude,but there is a certain phase shift phenomenon. It is therefore suggested that linear stack technology should be used when the requirements of both waveform quality and time precision are high. However,the selection of the stack method when the airgun source excitation is limited should be emphasized. If high fidelity is required, the S-transform stack method should be selected; if the required time is high,accuracy can be selected by phase-weighted stack method to achieve reasonable extraction of weak signals. 展开更多
关键词 Airgun sOURCE WEAK signal extraction Linear sTACK Phase-weighted sTACK s-TRANsFORM sTACK
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Non Ideal Schottky Barrier Diode’s Parameters Extraction and Materials Identification from Dark I-V-T Characteristics
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作者 M. Bashahu D. Ngendabanyikwa P. Nyandwi 《Journal of Modern Physics》 2022年第3期285-300,共16页
Several parameters of a commercial Si-based Schottky barrier diode (SBD) with unknown metal material and semiconductor-type have been investigated in this work from dark forward and reverse I-V characteristics in the ... Several parameters of a commercial Si-based Schottky barrier diode (SBD) with unknown metal material and semiconductor-type have been investigated in this work from dark forward and reverse I-V characteristics in the temperature (T) range of [274.5 K - 366.5 K]. Those parameters include the reverse saturation current (I<sub>s</sub>), the ideality factor (n), the series and the shunt resistances (R<sub>s</sub> and R<sub>sh</sub>), the effective and the zero bias barrier heights (Φ<sub>B</sub> and Φ<sub>B0</sub>), the product of the electrical active area (A) and the effective Richardson constant (A**), the built-in potential (V<sub>bi</sub>), together with the semiconductor doping concentration (N<sub>A</sub> or N<sub>D</sub>). Some of them have been extracted by using two or three different methods. The main features of each approach have been clearly stated. From one parameter to another, results have been discussed in terms of structure performance, comparison on one another when extracted from different methods, accordance or discordance with data from other works, and parameter’s temperature or voltage dependence. A comparison of results on Φ<sub>B</sub>, ΦB0</sub>, n and N<sub>A</sub> or N<sub>D</sub> parameters with some available data in literature for the same parameters, has especially led to clear propositions on the identity of the analyzed SBD’s metal and semiconductor-type. 展开更多
关键词 sBD Dark Forward and Reverse I-V-T Characteristics Different Parameters extraction Methods Identification of the structure’s Metal and semiconductor-Type
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Study on the Inhibitory Mechanism of Sophora japonica N-hexane Extract on Microcystis aeruginosa 被引量:4
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作者 周晓见 夏洁 +3 位作者 靳翠丽 缪莉 董昆明 封克 《Agricultural Science & Technology》 CAS 2011年第10期1543-1546,共4页
[Objective] The research aimed to analyze the inhibitory mechanism of Sophora japonica n-hexane extract which significantly inhibited Microcystis aeruginosa in the prior research.[Method] S.japonica n-hexane extract w... [Objective] The research aimed to analyze the inhibitory mechanism of Sophora japonica n-hexane extract which significantly inhibited Microcystis aeruginosa in the prior research.[Method] S.japonica n-hexane extract was used to treat M.aeruginosa.By inspecting chlorophyll a content,protein content,cell membrane permeability and superoxide dismutase(SOD) activity,the inhibitory mechanism of S.japonica n-hexane extract on M.aeruginosa was analyzed initially.[Result] S.japonica n-hexane extract destroyed the cell membrane system of M.aeruginosa,and increased the cell membrane permeability.The contents of chlorophyll a and protein respectively declined to 10% and 50% of that in the control group after cultivated for 7 d,which indicated the photosynthetic reaction system of M.aeruginosa was destroyed.In addition,under the effect of S.japonica n-hexane extract,SOD activity of M.aeruginosa increased in the early period and decreased in the latter period.[Conclusion] The possible inhibitory mechanism of S.japonica n-hexane extract on M.aeruginosa was destroying the cell membrane to increase the membrane permeability;destroying the photosynthetic reaction system to decrease the contents of photosynthetic pigment and protein;making SOD activity showing the phased variation. 展开更多
关键词 s.japonica M.aeruginosa N-hexane extract Inhibitory mechanism
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Comparison of Molluscicide Activity of Ethanol Extract of Sapium sebiferum,Pterocarya stenoptera and Cryptomeria fortunei
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作者 罗坤水 李闪金 +2 位作者 徐林初 余能富 邹峥嵘 《Agricultural Science & Technology》 CAS 2011年第2期256-257,261,共3页
[Objective] The aim was to compare the molluscicide activity of ethanol extract of Sapium sebiferum,Pterocarya stenoptera and Cryptomeria fortunei.[Method] The molluscicide activity of ethanol extract of S.sebiferum,P... [Objective] The aim was to compare the molluscicide activity of ethanol extract of Sapium sebiferum,Pterocarya stenoptera and Cryptomeria fortunei.[Method] The molluscicide activity of ethanol extract of S.sebiferum,P.stenoptera and C.fortunei was determined through poison test of Oncomelania hupensis in laboratory.[Result] S.sebiferum,P.stenoptera and C.fortunei had certain molluscicide effect,and S.sebiferum and C.fortunei had better effect with little difference than P.stenoptera;ethanol could extract the effective molluscicide component from plant more completely,and its molluscicide effect was better than that of plant infusion.[Conclusion] Our study could provide theory reference for the plant selection of controlling O.hupensis ecologically. 展开更多
关键词 Ethanol extract Killing O.hupensis s.sebiferum P.stenoptera C.fortunei
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