期刊文献+
共找到1,265篇文章
< 1 2 64 >
每页显示 20 50 100
Reduction Discoloration of Reactive Dyed Cotton Waste and Chemical Recycling via Ionic Liquid
1
作者 Aline Ferreira Knihs Larissa Klen Aragão +2 位作者 Miguel Angelo Granato Andrea Cristiane Krause Bierhalz Rita de Cassia Siqueira Curto Valle 《Journal of Renewable Materials》 EI CAS 2024年第9期1557-1571,共15页
The textile industry generates large volumes of waste throughout its production process.Most of this waste is colored,therefore,discoloration is an important step toward recycling and reusing this waste.This study foc... The textile industry generates large volumes of waste throughout its production process.Most of this waste is colored,therefore,discoloration is an important step toward recycling and reusing this waste.This study focused on the chemical reductive discoloration of textile waste composed of cotton dyed with reactive dye.The experimental design demonstrated the significant influence of the concentration of reducing agent and time of reaction on the degree of whiteness of the cotton fibers.The concentration of the alkaline agent was not significant in the process.The optimization of the reaction conditions lead to Berger degree of 50.5±3.5.The discolored cotton was chemically recycled through dissolution in ionic liquid 1-ethyl-3-methylimidazolium chloride and regeneration in film form in water.The microstructure of the regenerated cellulose films was evaluated by Scanning Electron Microscopy(SEM)indicating complete dissolution and uniform regeneration.The discoloration process reduced the polymerization degree and crystallinity index of the cotton fibers but retained the cellulose I structure.The dissolution and cellulose regeneration process results in transparent films with an amorphous structure.The thermal behavior,evaluated by thermogravimetric analysis,indicated that residues and regenerated film presented a main decomposition step.The maximum decomposition rate temperature of the regenerated films was approximately 40℃lower than the cotton fibers,which correlates well with the reduction in polymerization degree and amorphous structure.In general,the study demonstrated that textile cotton waste dyed with reactive dyes can be chemically discolored to form transparent and amorphous films,contributing to the development of sustainable strategies for the textile industry. 展开更多
关键词 Reactive dyed cotton waste reactive discoloration ionic liquid dissolution and regeneration recycling and reusing
下载PDF
Adsorptive Properties of Dyes to Cellulosic Sheet and Discoloration of Dye Solution by UV-ray Irradiation 被引量:4
2
作者 Zhou Yu Iida Ikuho +1 位作者 Minato Kazuya Kurosu Hiroshi 《Forestry Studies in China》 CAS 2005年第2期19-25,共7页
The adsorptive properties and selectivity of dyes and water molecules to cellulosic sheet, dependence of adsorptive properties of dyes on the concentration of dye solution, and discoloration of the dye solution due to... The adsorptive properties and selectivity of dyes and water molecules to cellulosic sheet, dependence of adsorptive properties of dyes on the concentration of dye solution, and discoloration of the dye solution due to the UV-ray irradiation were determined for 18 kinds of commercial dyes. The results are as follows: 1) the adsorptive properties of dyes to cellulose sheet differed greatly, but did not depend on the dye types such as acidic, basic and so on; 2) adsorptive properties of dyes to cellulosic sheet de- pended on the concentration of dye solution and were classified into 4 types: concentration-independent, increasing or decreasing with dye concentration, and having a maximum. This classification was irrelevant to the dye types; 3) the irradiation of UV-ray did not cause significant discoloration of dye solution itself, which suggested that wood components as well as dye molecules influence the discoloration of wood. 展开更多
关键词 dyed wood discoloration adsorptive property DYE
下载PDF
Discoloration of Congo Red by Rod-Plate Dielectric Barrier Discharge Processes at Atmospheric Pressure 被引量:4
3
作者 武海霞 方志 +2 位作者 周侗 陆晨 徐炎华 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期500-505,共6页
A dielectric barrier discharge (DBD) reactor with a rod-plate electrode configuration was used for the oxidative decomposition of Congo red dye in an aqueous solution. Plasma was generated in the gas space above the... A dielectric barrier discharge (DBD) reactor with a rod-plate electrode configuration was used for the oxidative decomposition of Congo red dye in an aqueous solution. Plasma was generated in the gas space above the water interface under atmospheric pressure. Discharge characteristics were analyzed by voltage-current waveforms. Effects of applied voltage, initial conductivity, and initial concentration were also analyzed. Congo red discoloration increased with increased applied voltage and decreased conductivity. The initial conductivity significantly influenced the Congo red discoloration. Under the same conditions, the highest discoloration rate was obtained at 25 mg/L. The presence of ferrous ions in the solutions had a substantial positive effect on Fenton dye degradation and flocculation. At an applied voltage of 20 kV, about 100% of dye was degraded after 4 min of Fe^2+/DBD treatment. Results showed that adding a certain dosage of hydrogen peroxide to the wastewater could enhance the discoloration rate. Possible pathways of Congo red discoloration by DBD plasma were proposed based on GC/MS, FTIR, and UV-vis spectroscopy analyses. 展开更多
关键词 dielectric barrier discharge (DBD) Congo red (CR) discoloration wastewater treatment
下载PDF
Correlation of discoloration and biomechanical properties in porcine sclera induced by genipin 被引量:2
4
作者 Tai-Xiang Liu Xin Luo +2 位作者 Yu-Wei Gu Bin Yang Zheng Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第4期621-625,共5页
·AIM: To study the feasibility of using the discoloration to evaluate the biomechanical properties after treating with genipin.·METHODS: Porcine cadaver eyes were treated for30 min with 1.0%(by w/v) genipin.... ·AIM: To study the feasibility of using the discoloration to evaluate the biomechanical properties after treating with genipin.·METHODS: Porcine cadaver eyes were treated for30 min with 1.0%(by w/v) genipin. Untreated samples were used as controls. After treatment, scleral strips of4.0 ×10.0-mm2 were cut. The denaturation temperature(Td) measurement and stress-strain test were performed after taking photograph to analyze the color.·RESULTS: Within 24 h after treating with genipin, the sclera exhibited a bluish color which became deeper with time. And the denaturation temperature also was increased gradually. Compared with untreated groups, at1, 6, 12, 24 and 36 h after treatment, the ultimate stress were increased by 56%, 153%, 173%, 225% and 211%respectively. The Young’s modulus at 10% strain also increased by 170%, 246%, 264%, 389% and 288%respectively. There were strong correlation between the discoloration and the biomechanical properties(ΔE-Ultimate stress:R2=0.892, P =0.00; ΔE-Young’s modulus:R2=0.602, P =0.00).·CONCLUSION: Genipin could be used to strengthen collagen gradually in a relatively short time span. And the biomechanical properties could be reliably evaluated via simple visible discoloration. 展开更多
关键词 GENIPIN CROSSLINKING SCLERA biomechanics discoloration
下载PDF
Effect of drying methods on the discoloration of three major domestic softwood species in Korea 被引量:2
5
作者 Ho-yang Kang 《Forestry Studies in China》 CAS 2006年第3期48-50,共3页
Japanese pine, Korean pine and larch are three major softwood species in Korea. Their colors are relatively light, thus easily discolored due to drying and UV irradiation. In this study, they were dried with five diff... Japanese pine, Korean pine and larch are three major softwood species in Korea. Their colors are relatively light, thus easily discolored due to drying and UV irradiation. In this study, they were dried with five different drying methods, steam treated and exposed to weathering. Their colors were measured using a spectrophotometer and comparisons made both among species and drying methods. For Japanese and Korean pines, high temperature dried and steam-dried specimens showed distinct color differences compared with the controls. Steam treatment discolored the dried specimens of Japanese and Korean pines but did not discolor those of larch. After weathering for 144 days the specimens of Japanese pine showed slight color differences among drying methods. 展开更多
关键词 discoloration drying method steam treatment WEATHERING SPECTROPHOTOMETER
下载PDF
Effects of gold plating on the resistance to high temperature discoloration of the cavity for ceramic packages 被引量:2
6
作者 ZhanhuaWang ZhuoshenShen DaobinMu 《Journal of University of Science and Technology Beijing》 CSCD 2004年第1期52-56,共5页
The effects of thickness and types of gold plating on the resistance to hightemperature discoloration of gold plating on cavity surface of ceramic package were investigated. Itwas found that the thicker gold plating, ... The effects of thickness and types of gold plating on the resistance to hightemperature discoloration of gold plating on cavity surface of ceramic package were investigated. Itwas found that the thicker gold plating, the less discoloration degree for ceramic packages.Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide goldplating. The relationship between the gold plating thickness and the amount of diffused Ni to thegold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃ for 15 minwas also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Coplating systems, respectively, no discoloration was observed on the gold plating surface of cavity,and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Coto the gold plating is 0.04%. 展开更多
关键词 CAVITY discoloration gold plating high temperature aging ceramic package
下载PDF
Evaluation of Teeth Discoloration Induced by Endomethasone, AH+, Canason and Apexit Paste 被引量:1
7
作者 Nexhmije Ajeti Teuta Pustina-Krasniqi +3 位作者 Tringa Kelmendi Arben Murtezani Violeta Vula Teuta Bicaj 《Open Journal of Stomatology》 2014年第12期507-517,共11页
Objective: The aim of this study was to investigate, in vitro, the color changes of the teeth, induced by endodontic sealers. Materials and Methods: Forty-five mature maxillary and mandibular anterior teeth, extracted... Objective: The aim of this study was to investigate, in vitro, the color changes of the teeth, induced by endodontic sealers. Materials and Methods: Forty-five mature maxillary and mandibular anterior teeth, extracted for periodontal reasons, were collected. After the chemo-mechanical instrumentation of the root canal, teeth were filled with four endodontic sealers (Endomethason, AH+, Canason and Apexit). Depending on canal sealers and the CEJ (Cement Enamel Junction), teeth were divided into 8 experimental groups (n = 5) and one control group/CG (n = 5). Teeth color changes (L*a*b*/CIE Commission Internationaled’ Eclaraige) were determinated by a spectrophotometer Vita Easyshade in 4 stages (Baseline, Week 0, 4 and 12). Results: Between the EOCEJ and CG for the parameter L*, there was a statistical significance (p 0.05). The L*a*b* results were: L* (83.6 ± 4.8 → 83.6 ± 4.9);a* (﹣2.68 ± 1.02 → ﹣1.12 ± 0.72) and b* (20.2 ± 4.5 → 24.4 ± 4.2). Conclusions: All endodontic sealers may cause teeth discoloration. 展开更多
关键词 discoloration ENDODONTIC Sealers SPECTROPHOTOMETER
下载PDF
Effects of gold plating on the resistance to high temperature discoloration of the cavity for ceramic packages
8
作者 WANG Zhanhua, SHEN Zhuoshen, and MU Daobin 《Rare Metals》 SCIE EI CAS CSCD 2004年第1期58-58,共1页
The effects of thickness and types of gold plating on the resistance to high temperature discoloration of gold plating on cavity surface of ceramic package were investigated. It was found that the thicker gold plating... The effects of thickness and types of gold plating on the resistance to high temperature discoloration of gold plating on cavity surface of ceramic package were investigated. It was found that the thicker gold plating, the less discoloration degree for ceramic packages. Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide gold plating. The relationship between the gold plating thickness and the amount of diffused Ni to the gold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃for 15 min was also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Co plating systems, respectively, no discoloration was observed on the gold plating surface of cavity, and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Co to the gold plating is 0.04%. 展开更多
关键词 CAVITY discoloration gold plating high temperature aging ceramic package
下载PDF
Discoloration on Methylene Blue Solutions by Direct and Catalytic Ozonation
9
作者 Antonio D. Rodriguez-Lopez Jose Garcia-Garrido +1 位作者 Cynthia Perez-Ramiro Esperanza M. Garcia-Castello 《Journal of Materials Science and Chemical Engineering》 2013年第5期33-38,共6页
During textile manufacturing, huge amounts of wastewaters characterized by removed impurities and high concentrations of dye are produced. These wastewaters cause several problems when they are discharged to the envir... During textile manufacturing, huge amounts of wastewaters characterized by removed impurities and high concentrations of dye are produced. These wastewaters cause several problems when they are discharged to the environment. The use of ozone in wastewater treatment results of interest. In this work we propose to assess the discoloration rate of different synthetic wastewaters as a function of pH, dye concentration (methylene blue (MB)) and reaction time. A comparison of discoloration rate between conventional ozonation and catalytic ozonation salts of copper, zinc, silver and nickel was also performed. For the optimization of the ozonation process of colored solutions, it was used a central composite experimental design with five replicates of the center point resulting to evaluate the influence of the independent variables at different ranges of pH, [MB] and time. In the catalyst-assisted ozonation, [MB], pH and the reaction time were fixed to 100 mg/L, 5.5 and 15 min, respectively. The optimized experimental conditions to provide maximum discoloration were pH=3.3;[MB]=8.6 mg/L and time=74.3 min. Regarding the catalyst-assisted ozonation, it was found that CuSO4 catalyst gave better color reduction if compared with other catalysts assayed. 展开更多
关键词 TEXTILE WASTEWATER METHYLENE BLUE discoloration OZONATION Catalytic
下载PDF
Scheme Based on Multi-Level Patch Attention and Lesion Localization for Diabetic Retinopathy Grading 被引量:1
10
作者 Zhuoqun Xia Hangyu Hu +4 位作者 Wenjing Li Qisheng Jiang Lan Pu Yicong Shu Arun Kumar Sangaiah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期409-430,共22页
Early screening of diabetes retinopathy(DR)plays an important role in preventing irreversible blindness.Existing research has failed to fully explore effective DR lesion information in fundus maps.Besides,traditional ... Early screening of diabetes retinopathy(DR)plays an important role in preventing irreversible blindness.Existing research has failed to fully explore effective DR lesion information in fundus maps.Besides,traditional attention schemes have not considered the impact of lesion type differences on grading,resulting in unreasonable extraction of important lesion features.Therefore,this paper proposes a DR diagnosis scheme that integrates a multi-level patch attention generator(MPAG)and a lesion localization module(LLM).Firstly,MPAGis used to predict patches of different sizes and generate a weighted attention map based on the prediction score and the types of lesions contained in the patches,fully considering the impact of lesion type differences on grading,solving the problem that the attention maps of lesions cannot be further refined and then adapted to the final DR diagnosis task.Secondly,the LLM generates a global attention map based on localization.Finally,the weighted attention map and global attention map are weighted with the fundus map to fully explore effective DR lesion information and increase the attention of the classification network to lesion details.This paper demonstrates the effectiveness of the proposed method through extensive experiments on the public DDR dataset,obtaining an accuracy of 0.8064. 展开更多
关键词 DDR dataset diabetic retinopathy lesion localization multi-level patch attention mechanism
下载PDF
Discoloration Range and Shroud Image Depth Values Cannot Be Satisfied by the Same Proton Energy
11
作者 Giovanni Fazio 《Open Journal of Applied Sciences》 2023年第8期1224-1232,共9页
The radiative hypothesis has been revisited showing other characteristics, produced by the protons used as dyes in total disagree with the ones of the Body Image that appears on the Shroud of Turin. Our investigations... The radiative hypothesis has been revisited showing other characteristics, produced by the protons used as dyes in total disagree with the ones of the Body Image that appears on the Shroud of Turin. Our investigations highlight that for the protons to reach 3.7 cm in air, the distance that measures the range of discoloration effects, must be emitted with an energy of about 1.5 MeV using Wilson and Brobeck’s empirical formula and 1.35 MeV using Bethe’s. This last formula provides a result closer to reality. Bethe shows that the penetration depth is greater than that calculated empirically. Such a value of proton energy (1.35 MeV) makes it possible to satisfy the discoloration effects range for the Shroud but it is incompatible with a depth of penetration in linen that is only 200 nm. Moreover, using the same subatomic particles, we obtained on the colored linen a distribution of energy represented by regression but not linear. Thus, also the possible I(z) correlation, between color intensity and body-sheet distance, which should be due to the oxidizing action of protons, does not agree with that extracted from the Shroud of Turin. 展开更多
关键词 Shroud of Turin Body Image Formation Radiative Hypothesis Proton Model discoloration Effects Range
下载PDF
Deep neural network based on multi-level wavelet and attention for structured illumination microscopy
12
作者 Yanwei Zhang Song Lang +2 位作者 Xuan Cao Hanqing Zheng Yan Gong 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期12-23,共12页
Structured illumination microscopy(SIM)is a popular and powerful super-resolution(SR)technique in biomedical research.However,the conventional reconstruction algorithm for SIM heavily relies on the accurate prior know... Structured illumination microscopy(SIM)is a popular and powerful super-resolution(SR)technique in biomedical research.However,the conventional reconstruction algorithm for SIM heavily relies on the accurate prior knowledge of illumination patterns and signal-to-noise ratio(SNR)of raw images.To obtain high-quality SR images,several raw images need to be captured under high fluorescence level,which further restricts SIM’s temporal resolution and its applications.Deep learning(DL)is a data-driven technology that has been used to expand the limits of optical microscopy.In this study,we propose a deep neural network based on multi-level wavelet and attention mechanism(MWAM)for SIM.Our results show that the MWAM network can extract high-frequency information contained in SIM raw images and accurately integrate it into the output image,resulting in superior SR images compared to those generated using wide-field images as input data.We also demonstrate that the number of SIM raw images can be reduced to three,with one image in each illumination orientation,to achieve the optimal tradeoff between temporal and spatial resolution.Furthermore,our MWAM network exhibits superior reconstruction ability on low-SNR images compared to conventional SIM algorithms.We have also analyzed the adaptability of this network on other biological samples and successfully applied the pretrained model to other SIM systems. 展开更多
关键词 Super-resolution reconstruction multi-level wavelet packet transform residual channel attention selective kernel attention
下载PDF
An Expert System to Detect Political Arabic Articles Orientation Using CatBoost Classifier Boosted by Multi-Level Features
13
作者 Saad M.Darwish Abdul Rahman M.Sabri +1 位作者 Dhafar Hamed Abd Adel A.Elzoghabi 《Computer Systems Science & Engineering》 2024年第6期1595-1624,共30页
The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orient... The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orientation detection.Political articles(especially in the Arab world)are different from other articles due to their subjectivity,in which the author’s beliefs and political affiliation might have a significant influence on a political article.With categories representing the main political ideologies,this problem may be thought of as a subset of the text categorization(classification).In general,the performance of machine learning models for text classification is sensitive to hyperparameter settings.Furthermore,the feature vector used to represent a document must capture,to some extent,the complex semantics of natural language.To this end,this paper presents an intelligent system to detect political Arabic article orientation that adapts the categorical boosting(CatBoost)method combined with a multi-level feature concept.Extracting features at multiple levels can enhance the model’s ability to discriminate between different classes or patterns.Each level may capture different aspects of the input data,contributing to a more comprehensive representation.CatBoost,a robust and efficient gradient-boosting algorithm,is utilized to effectively learn and predict the complex relationships between these features and the political orientation labels associated with the articles.A dataset of political Arabic texts collected from diverse sources,including postings and articles,is used to assess the suggested technique.Conservative,reform,and revolutionary are the three subcategories of these opinions.The results of this study demonstrate that compared to other frequently used machine learning models for text classification,the CatBoost method using multi-level features performs better with an accuracy of 98.14%. 展开更多
关键词 Political articles orientation detection CatBoost classifier multi-level features context-based classification social networks machine learning stylometric features
下载PDF
Construction of a Multi-Level Strategic System for Cultivating Cultural Industry Management Talents in Colleges and Universities
14
作者 Zhenzhen Hu Tao Zhou 《Journal of Contemporary Educational Research》 2024年第10期75-82,共8页
Through SWOT(strengths,weaknesses,opportunities,and threats)and PEST(political,economic,social,and technological)analysis,this study discusses the construction of a multi-level strategic system for the cultivation of ... Through SWOT(strengths,weaknesses,opportunities,and threats)and PEST(political,economic,social,and technological)analysis,this study discusses the construction of a multi-level strategic system for the cultivation of cultural industry management talents in colleges and universities.First of all,based on SWOT analysis,it is found that colleges and universities have rich educational resources and policy support,but they face challenges such as insufficient practical teaching and intensified international competition.External opportunities come from the rapid development of the cultivation of cultural industry management talents and policy promotion,while threats come from global market competition and talent flow.Secondly,PEST analysis reveals the key factors in the macro-environment:at the political level,the state vigorously supports the cultivation of cultural industry management talents;at the economic level,the market demand for cultural industries is strong;at the social level,the public cultural consumption is upgraded;at the technological level,digital transformation promotes industry innovation.On this basis,this paper puts forward a multi-level strategic system covering theoretical education,practical skill improvement,interdisciplinary integration,and international vision training.The system aims to solve the problems existing in talent training in colleges and universities and cultivate high-quality cultural industry management talents with theoretical knowledge,practical skills,and global vision,so as to adapt to the increasingly complex and diversified cultural industry management talents market demand and promote the long-term development of the industry. 展开更多
关键词 Cultural industry management talents Personnel training multi-level strategic system
下载PDF
Multi-level access control model for tree-like hierarchical organizations
15
作者 於光灿 李瑞轩 +3 位作者 卢正鼎 Mudar Sarem 宋伟 苏永红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期393-396,共4页
An access control model is proposed based on the famous Bell-LaPadula (BLP) model.In the proposed model,hierarchical relationships among departments are built,a new concept named post is proposed,and assigning secur... An access control model is proposed based on the famous Bell-LaPadula (BLP) model.In the proposed model,hierarchical relationships among departments are built,a new concept named post is proposed,and assigning security tags to subjects and objects is greatly simplified.The interoperation among different departments is implemented through assigning multiple security tags to one post, and the more departments are closed on the organization tree,the more secret objects can be exchanged by the staff of the departments.The access control matrices of the department,post and staff are defined.By using the three access control matrices,a multi granularity and flexible discretionary access control policy is implemented.The outstanding merit of the BLP model is inherited,and the new model can guarantee that all the information flow is under control.Finally,our study shows that compared to the BLP model,the proposed model is more flexible. 展开更多
关键词 multi-level access control hierarchical organization multiple security tags
下载PDF
Aseptic Seedling and Rapid Propagation of Ludisia discolor
16
作者 李宏杨 刘扬 +1 位作者 陈冠铭 杨志娟 《Agricultural Science & Technology》 CAS 2016年第11期2473-2476,2482,共5页
[Objective] This study was conducted to establish a system for aseptic seeding and rapid propagation of a wild Chinese herbal medicine Ludisia discolor. [Method] The seeds of L. discolor were germinated in four differ... [Objective] This study was conducted to establish a system for aseptic seeding and rapid propagation of a wild Chinese herbal medicine Ludisia discolor. [Method] The seeds of L. discolor were germinated in four different culture media MS, 1/2MS, Hyponex No.1 (3.0 g/L), and 1/2 Hyponex No.1 (1.5 g/L), and the ger- mination rate was calculated 80 d later to select the optimal medium for seed ger- mination of L. discolor. Then, by culturing the protocorms and buds of L. discolor in the media supplemented with different hormone combinations (6-BA and NAA) or organic substrates (potato juice, banana juice and coconut milk), the optimal medi- um compositions for multiplication and .differentiation, seedling hardening and rooting of L. discolor were respectively determined. [Result] After 80 d of dark culture, 86.67% of the seeds inoculated into the medium 1/2 Hyponex No.1 germinated and developed into protocorms, proving 1/2 Hyponex No.1 was most suitable for seed germination of L. discolor among the four basic media, while MS medium had the worst effects. In culture medium of 1/2 Hyponex No.1+2.0 mg/L 6-BA+100 ml/L co- conut milk supplemented with 0.4 or 0.6 mg/L NAA, a mixed body of protocorms and small buds were induced after being cultured for 45 d, and the multiplication rate was 6.11, which was higher than that in the medium supplied with 0.2 or 0.8 mg/L NAA. By adding 10% potato juice, 10% banana juice or 100 ml/L coconut milk into Hyponex No.1+1.0 mg/L NAA, it was found that 10% banana juice had better effects in hardening and rooting of L. discolor planlets than 10% potato juice and 100 ml/L coconut milk. The small buds grew into plantlets about 80 d later in the medium with banana juice, the rooting rate was 93.33%, and the plantlet height was 7.19 cm. After hardening-culture for 10 d in a greenhouse, the L. discolor plantlets were transplanted into the mixed matrix of peat soil and lava (at a ratio of 3:1), and 91.7% of them survived 60 d later. [Conclusion] A relatively perfect propa- gation system of L. discolor was established by using aseptic seeds as explants in this study, which can be used for the protection of L. discolor germplasm resources, seedling propagation and industrial development. 展开更多
关键词 Ludisia discolor Aseptic seeding Rapid propagation Organic compounds
下载PDF
Shape retrieval using multi-level included angle functions-based Fourier descriptor 被引量:1
17
作者 徐国清 穆志纯 徐烨 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期22-26,共5页
An effective shape signature namely multi-level included angle functions MIAFs is proposed to describe the hierarchy information ranging from global information to local variations of shape.Invariance to rotation tran... An effective shape signature namely multi-level included angle functions MIAFs is proposed to describe the hierarchy information ranging from global information to local variations of shape.Invariance to rotation translation and scaling are the intrinsic properties of the MIAFs.For each contour point the multi-level included angles are obtained based on the paired line segments derived from unequal-arc-length partitions of contour.And a Fourier descriptor derived from multi-level included angle functions MIAFD is presented for efficient shape retrieval.The proposed descriptor is evaluated with the standard performance evaluation method on three shape image databases the MPEG-7 database the Kimia-99 database and the Swedish leaf database. The experimental results of shape retrieval indicate that the MIAFD outperforms the existing Fourier descriptors and has low computational complexity.And the comparison of the MIAFD with other shape description methods also shows that the proposed descriptor has the highest precision at the same recall value which verifies its effectiveness. 展开更多
关键词 shape description image retrieval multi-level included angle function Fourier descriptor
下载PDF
Seasonal Dynamics of Nitrogen and Phosphorus in Water and Sediment of A Multi-level Ditch System in Sanjiang Plain,Northeast China 被引量:6
18
作者 GUO Le MA Keming 《Chinese Geographical Science》 SCIE CSCD 2011年第4期437-445,共9页
The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasona... The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasonal dynamics of nitrogen (N) and phosphorus (P) transportation in the ditch system and the role of different ditch size is thus crucial for water pollution control of the rivers in the Sanjiang Plain.In this study,an investigation was conducted in the Nongjiang watershed of the Sanjiang Plain to study the nutrient variation and the correlation between water and sediments in the ditch system in terms of ditch level.Water and sediments samples were collected in each ditch level in growing season at regular intervals (once per month),and TN,NO 3--N,NH 4+-N,TP,and PO 4 3--P were analyzed.The results show that nutrient contents in water were higher in June and July,especially in July,the contents of TN and TP were 3.21mg/L and 0.84mg/L in field ditch,4.04mg/L and 1.06mg/L in lateral ditch,2.46mg/L and 0.70mg/L in branch ditch,1.92mg/L and 0.63mg/L in main ditch,respectively.In August and September,the nutrient contents in the water were relatively lower.The peak value of nutrient in ditch water had been moving from the field ditch to the main ditch over time,showing a remarkable impact of ditch system on river water environment.The nutrient transfer in ditch sediments could only be found in rainfall season.Nutrient contents in ditch sediment had effect on that in ditch water,but nutrients in ditch water and sediments had different origination.Ditch management in terms of the key fac-tors is hence very important for protecting river water environment. 展开更多
关键词 multi-level ditch system nitrogen PHOSPHORUS spatio-temporal variation drainage water sediment
下载PDF
A Mandatory Access Control Framework in Virtual Machine System with Respect to Multi-level Security Ⅱ:Implementation 被引量:5
19
作者 刘谦 王观海 +2 位作者 翁楚良 骆源 李明禄 《China Communications》 SCIE CSCD 2011年第2期86-94,共9页
This paper is a continuation of our last paper [1] which describes the theory of Virt-BLP model. Based on Virt-BLP model,this paper implements a mandatory access control(MAC) framework applicable to multi-level securi... This paper is a continuation of our last paper [1] which describes the theory of Virt-BLP model. Based on Virt-BLP model,this paper implements a mandatory access control(MAC) framework applicable to multi-level security(MLS) in Xen. The Virt-BLP model is the theoretical basis of this MAC framework,and this MAC framework is the implementation of Virt-BLP model. Our last paper focuses on Virt-BLP model,while this paper concentrates on the design and implementation of MAC framework. For there is no MAC framework applicable to MLS in virtual machine system at present,our MAC framework fills the blank by applying Virt-BLP model to Xen,which is better than current researches to guarantee the security of communication between virtual machines(VMs) . The experimental results show that our MAC framework is effective to manage the communication between VMs. 展开更多
关键词 virt-BLP model MAC framework multi-level security XEN
下载PDF
A Multi-level Approach for Complex Fault Isolation Based on Structured Residuals 被引量:4
20
作者 叶鲁彬 石向荣 梁军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期462-472,共11页
In industrial processes,there exist faults that have complex effect on process variables.Complex and simple faults are defined according to their effect dimensions.The conventional approaches based on structured resid... In industrial processes,there exist faults that have complex effect on process variables.Complex and simple faults are defined according to their effect dimensions.The conventional approaches based on structured residuals cannot isolate complex faults.This paper presents a multi-level strategy for complex fault isolation.An extraction procedure is employed to reduce the complex faults to simple ones and assign them to several levels.On each level,faults are isolated by their different responses in the structured residuals.Each residual is obtained insensitive to one fault but more sensitive to others.The faults on different levels are verified to have different residual responses and will not be confused.An entire incidence matrix containing residual response characteristics of all faults is obtained,based on which faults can be isolated.The proposed method is applied in the Tennessee Eastman process example,and the effectiveness and advantage are demonstrated. 展开更多
关键词 multi-level structured residuals principal component analysis complex fault isolation Tennessee Eastman process
下载PDF
上一页 1 2 64 下一页 到第
使用帮助 返回顶部