期刊文献+
共找到3,535篇文章
< 1 2 177 >
每页显示 20 50 100
Surface Water Quality Profiling Using Physicochemical Parameters in Open Defecation Free and Non-Open Defecation Free Local Government Areas in Benue State, Nigeria
1
作者 Moses T. Asoo Celestine U. Aguoru +1 位作者 Innocent O. Ogbonna Hyacinth O.A. Oluma 《Open Journal of Modern Hydrology》 CAS 2024年第3期174-191,共18页
Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 ... Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 mg/L), Na (28.72 mg/L), Ca (28.94 mg/L), Mg (17.50 mg/L), Cl (11.65 mg/L), TSS (6.27 mg/L), TDS (104.23 mg/L), BOD (2.83 mg/L) and F (0.87 mg/L) were below WHO standards irrespective of their defecation status. The values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTU), dissolved oxygen (DO) (5.32 mg/L), chemical oxygen demand (COD) (445.50 mg/L), K (125.06 mg/L), PO4 (0.78 mg/L) and Fe (0.57 mg/L) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pollution of the water sources by organic matter. 展开更多
关键词 Open Defecation Surface Water Water quality Standard Physicochemical parameters
下载PDF
Does exposure to computers affect the routine parameters of semen quality? 被引量:6
2
作者 Yue-Lian Sun Wei-Jin Zhou Jun-Qing Wu Er-Sheng Gao 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第3期263-266,共4页
Aim: To assess whether exposure to computers harms the semen quality of healthy young men. Methods: A total of 178 subjects were recruited from two maternity and children healthcare centers in Shanghai, 91 with a hi... Aim: To assess whether exposure to computers harms the semen quality of healthy young men. Methods: A total of 178 subjects were recruited from two maternity and children healthcare centers in Shanghai, 91 with a history of exposure to computers (i.e., exposure for 20 h or more per week in the last 2 years) and 87 persons to act as control (no or little exposure to computers). Data on the history of exposure to computers and other characteristics were obtained by means of a structured questionnaire interview. Semen samples were collected by masturbation in the place where the semen samples were analyzed. Results: No differences in the distribution of the semen parameters (semen volume, sperm density, percentage of progressive sperm, sperm viability and percentage of normal form sperm) were found between the exposed group and the control group. Exposure to computers was not found to be a risk factor for inferior semen quality after adjusting for potential confounders, including abstinence days, testicle size, occupation, history of exposure to toxic substances. Conclusion: The present study did not find that healthy: men exposed to computers had inferior semen quality. (Asian J Andro12005 Sep; 7: 263-266) 展开更多
关键词 COMPUTER MAGNETIZATION electromagnetization male reproduction semen analysis semen quality semen parameters
下载PDF
Identification welding parameters using complex criteria of quality 被引量:3
3
作者 巴布金·亚历山大 常云龙 巴布金·伊戈 《China Welding》 EI CAS 2017年第4期1-9,共9页
In the present paper,the graphical method determination of optimal welding parameters of GMAW is described.Some quality complex criteria that are the ratio of weld sizes have been proposed. These criteria allow optimi... In the present paper,the graphical method determination of optimal welding parameters of GMAW is described.Some quality complex criteria that are the ratio of weld sizes have been proposed. These criteria allow optimizing the shape of the weld metal zone,reducing the likelihood of hot cracks formation,and reducing the stress concentration of the weld at the toe. In the proposed methodology,the earlier described equations connecting the welding parameters and the weld dimensions of mild and low-alloy steels are explored. Determination of the optimal welding parameters is carried out graphically taking into account the variance of the welding parameters. An example of using the proposed method destined to determine the optimum welding parameters is provided. It is shown that its accuracy is sufficiently good for a practical application. 展开更多
关键词 gas metal ARC WELDING INVERSE problem quality CRITERIA optimal WELDING parameters WELD dimensions
下载PDF
Modeling river water quality parameters using modified adaptive neuro fuzzy inference system 被引量:2
4
作者 Armin Azad Hojat Karami +2 位作者 Saeed Farzin Sayed-Farhad Mousavi Ozgur Kisi 《Water Science and Engineering》 EI CAS CSCD 2019年第1期45-54,共10页
Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm (EA) is a new technique for improv... Water quality is always one of the most important factors in human health. Artificial intelligence models are respected methods for modeling water quality. The evolutionary algorithm (EA) is a new technique for improving the performance of artificial intelligence models such as the adaptive neuro fuzzy inference system (ANFIS) and artificial neural networks (ANN). Attempts have been made to make the models more suitable and accurate with the replacement of other training methods that do not suffer from some shortcomings, including a tendency to being trapped in local optima or voluminous computations. This study investigated the applicability of ANFIS with particle swarm optimization (PSO) and ant colony optimization for continuous domains (ACOR) in estimating water quality parameters at three stations along the Zayandehrood River, in Iran. The ANFIS-PSO and ANFIS-ACOR methods were also compared with the classic ANFIS method, which uses least squares and gradient descent as training algorithms. The estimated water quality parameters in this study were electrical conductivity (EC), total dissolved solids (TDS), the sodium adsorption ratio (SAR), carbonate hardness (CH), and total hardness (TH). Correlation analysis was performed using SPSS software to determine the optimal inputs to the models. The analysis showed that ANFIS-PSO was the better model compared with ANFIS-ACOR. It is noteworthy that EA models can improve ANFIS' performance at all three stations for different water quality parameters. 展开更多
关键词 Water quality parameters ANFIS Evolutionary algorithm Particle SWARM OPTIMIZATION Ant COLONY OPTIMIZATION for continuous DOMAINS
下载PDF
Parameter selection and model research on remote sensing evaluation for nearshore water quality 被引量:1
5
作者 LEI Guibin ZHANG Ying +2 位作者 PAN Delu WANG Difeng FU Dongyang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第1期114-117,共4页
Using remote sensing technology for water quality evaluation is an inevitable trend in marine environmental monitoring. However, fewer categories of water quality parameters can be monitored by remote sensing technolo... Using remote sensing technology for water quality evaluation is an inevitable trend in marine environmental monitoring. However, fewer categories of water quality parameters can be monitored by remote sensing technology than the 35 specified in GB3097-1997 Marine Water Quality Standard. Therefore, we considered which parameters must be selected by remote sensing and how to model for water quality evaluation using the finite parameters. In this paper, focused on Leizhou Peninsula nearshore waters, we found N, P, COD, PH and DO to be the dominant parameters of water quality by analyzing measured data. Then, mathematical statistics was used to determine that the relationship among the five parameters was COD〉DO〉P〉N〉pH. Finally, five-parameter, fourparameter and three-parameter water quality evaluation models were established and compared. The results showed that COD, DO, P and N were the necessary parameters for remote sensing evaluation of the Leizhou Peninsula nearshore water quality, and the optimal comprehensive water quality evaluation model was the four- parameter model. This work may serve as a reference for monitoring the quality of other marine waters by remote sensing. 展开更多
关键词 main water quality parameters water quality parameter selection comprehensive water qualityevaluation model Leizhou Peninsula nearshore waters
下载PDF
Relationships between the surface quality of a single crystal copper ingot and the process parameters of a heated mould continuous casting method 被引量:1
6
作者 G.J.Xu Z.F.Ding +3 位作者 Y.T.Ding S.H.Kou G.L.Liu C.L.Feng 《China Foundry》 SCIE CAS 2004年第S1期62-66,共5页
The relationships between the surface quality of a single crystal copper ingot and the process parameters of heated mould continuous casting method were studied experimentally using our own design of horizontal heated... The relationships between the surface quality of a single crystal copper ingot and the process parameters of heated mould continuous casting method were studied experimentally using our own design of horizontal heated mould continuous casting apparatus, and the mechanism by which process parameters affect the surface quality of a single crystal copper ingot is analyzed in the present paper. The results show that the process parameters affect the surface quality of a pure copper ingot by affecting the position of the liquid-solid interface in the mould. The position of the liquid-solid interface in the mould must be controlled carefully within an appropriate range, which is determined through a series of experiments, in order to gain a single crystal copper ingot with good surface quality. 展开更多
关键词 heated mould continuous casting single crystal copper surface quality process parameter
下载PDF
Memory-Type Control Charts Through the Lens of Cost Parameters
7
作者 Sakthiseswari Ganasan You Huay Woon +1 位作者 Zainol Mustafa Dadasaheb G.Godase 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期1-10,共10页
A memory-type control chart utilizes previous information for chart construction.An example of a memory-type chart is an exponentially-weighted moving average(EWMA)control chart.The EWMA control chart is well-known an... A memory-type control chart utilizes previous information for chart construction.An example of a memory-type chart is an exponentially-weighted moving average(EWMA)control chart.The EWMA control chart is well-known and widely employed by practitioners for monitoring small and moderate process mean shifts.Meanwhile,the EWMA median chart is robust against outliers.In light of this,the economic model of the EWMA and EWMA median control charts are commonly considered.This study aims to investigate the effect of cost parameters on the out-of-control average run lengthðARL_(1)Þin implementing EWMA and EWMA median control charts.The economic model was used to compute the ARL_(1) parameter.The 14 input parameters were identified and the analysis was carried out based on the one-parameter-at-a-time basis.When the input parameters change based on a predetermined percentage,the ARL_(1) is affected.According to the results of the EWMA chart,nine input parameters had an effect andfive input parameters had no effect on the ARL_(1) parameter.Further,only seven of the 14 input parameters had an effect on the ARL_(1) of the EWMA median chart.However,the effect of each input parameter on the ARL_(1) was different.Moreover,the ARL_(1) for the EWMA median chart was smaller than the EWMA chart.This analysis is crucial to observe and determine the input parameters that have a significant impact on the ARL_(1) of the EMWA and EWMA median control charts.Hence,practitioners can obtain an overview of the influence of the input parameters on the ARL_(1) when implementing the EWMA and EWMA median control charts. 展开更多
关键词 Economic model average run length memory-type control chart cost parameters statistical quality control
下载PDF
Parameter selecting and quality predicting of spot welding based on artificial neural networks 被引量:1
8
作者 赵熹华 王宸煜 张若冰 《China Welding》 EI CAS 1998年第2期4-8,共5页
This paper proposes a procedure for using artificial neural networks (ANN) in spot welding , and establishes spot welding parameter selecting ANN systems and spot welding joint quality predicting ANN systems . It has ... This paper proposes a procedure for using artificial neural networks (ANN) in spot welding , and establishes spot welding parameter selecting ANN systems and spot welding joint quality predicting ANN systems . It has been proved that the ANN systems have high prediction precision , providing a new way of parameter selecting and quality predicting in spot welding . 展开更多
关键词 artificial neural networks resistance spot welding parameter selecting quality predicting
下载PDF
Effects of rigid gas permeable contact lens on morphological parameters and vision-related quality of life in keratoconus patients 被引量:2
9
作者 Yue Xu Yun Wang Xiao-Feng Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第11期1772-1781,共10页
AIM: To evaluate the effect of rigid gas permeable contact lens(RGP-CL) on corneal morphological parameters and vision-related quality of life in keratoconus(KC) patients.METHODS: Totally 57 eyes of 30 KC patients who... AIM: To evaluate the effect of rigid gas permeable contact lens(RGP-CL) on corneal morphological parameters and vision-related quality of life in keratoconus(KC) patients.METHODS: Totally 57 eyes of 30 KC patients who were followed-up for more than two years, including 17 RGP wearers(32 eyes) and 13 non-wearers(25 eyes) were retrospectively analyzed. Initial medical history and corneal topography were collected at baseline. Corneal topography, corneal aberration, optical coherence tomography, and vision-related quality of life questionnaires were performed at the last follow-up.RESULTS: According to corneal topography, increase of the flattest keratometric values was higher in RGP wearers than in non-wearers(P=0.038). The morphological parameters, including symmetry index of front corneal curvature(P=0.004) and Baiocchi-Calossi-Versaci index front(P=0.047), were lower in RGP wearers than in nonwearers. Vertical coma was smaller in RGP wearers than non-wearers in 3.0, 5.0, 6.0, and 7.0 mm pupil diameters, respectively(P<0.05). The environmental triggering domain of ocular surface disease index was worse in RGP wearers as compared to non-wearers(P=0.003). At the last followup, there were no significant differences in constituent ratios of KC progression, corneal thickness topography, epithelial thickness topography, morphological parameters of corneal topography, and other questionnaire scores between the two groups(all P>0.05).CONCLUSION: Long-term use of RGP does not worsen KC but may cause corneal epithelial remodeling to increase symmetry of corneal anterior surface, reduce corneal vertical coma and improve visual quality. However, RGP wearing causes a slight decrease in vision-related quality of life. The occurrence of ocular surface symptoms is mainly associated with environmental triggering factors. 展开更多
关键词 KERATOCONUS rigid gas permeable contact lens morphological parameters corneal aberration visionrelated quality of life
下载PDF
Understanding Seasonal and Spatial Variation of Water Quality Parameters in Mangrove Estuary of the Nyong River Using Multivariate Analysis (Cameroon Southern Atlantic Coast) 被引量:1
10
作者 Anselme Crépin Mama Willy Karol Abouga Bodo +2 位作者 Gisele Flodore Youbouni Ghepdeu Gordon Nwutih Ajonina Jules Rémi Ngoupayou Ndam 《Open Journal of Marine Science》 2021年第3期103-128,共26页
To evaluate the actual status of water quality and conclude on the mains source of pollution in the Nyong estuary River, seasonal and spatial variation of water quality parameters was interpreted by multivariate stati... To evaluate the actual status of water quality and conclude on the mains source of pollution in the Nyong estuary River, seasonal and spatial variation of water quality parameters was interpreted by multivariate statistical techniques (Principal Component analysis). Nine (09) environmental variables were monitored at four surface stations in the estuary for two seasonal cycles. The fieldwork was conducted from 2018 to 2019 during high tide and low <span style="letter-spacing:0.1pt;">tide for each survey. In situ physical parameters were measured for a total of</span> 64 samples (32 samples for each tide). The laboratory works consisted of some physicochemical analyses and processing of these data by descriptive <span style="letter-spacing:0.1pt;">and multidimensional statistical analyses. Temperature, suspended particle</span> matter, nitrate, nitrite and phosphate change significantly in the estuary with season (<i>p</i> < 0.05), while salinity, dissolved oxygen, pH, and ammonium do not vary significantly with season (<i>p</i> > 0.05). Principal Component analysis found temperature, salinity, pH, ammonium to be the most important parameters contributing to the fluctuations of surface water quality in the Nyong estuary during the dry seasons whereas suspended particle matter, nitrate, and phosphate are the most important parameters contributing to the fluctuation of surface water quality in the Nyong estuary during the rainy seasons. Based on spatial variation, the Principal Component analysis found that, suspended particle matter, nitrate and phosphate contribute to the fluctuation of surface water quality parameters upstream of the estuary while downstream salinity, pH, and ammonium contribute the most to the fluctuation of surface water quality. This study shows us the usefulness of multivariate statistical techniques used in assessing water quality data sets that would help us in un<span style="letter-spacing:0.1pt;">derstanding seasonal and spatial variations of water quality parameters to</span> manage estuarine systems. 展开更多
关键词 Water quality parameters Nyong Estuary Principal Component Analysis
下载PDF
Predictive Model for Cement Clinker Quality Parameters 被引量:1
11
作者 Nsidibe-Obong Ekpe Moses Sunday Boladale Alabi 《Journal of Materials Science and Chemical Engineering》 2016年第7期84-100,共17页
Managers of cement plants are gradually becoming aware of the need for soft sensors in product quality assessment. Cement clinker quality parameters are mostly measured by offline laboratory analysis or by the use of ... Managers of cement plants are gradually becoming aware of the need for soft sensors in product quality assessment. Cement clinker quality parameters are mostly measured by offline laboratory analysis or by the use of online analyzers. The measurement delay and cost, associated with these methods, are a concern in the cement industry. In this study, a regression-based model was developed to predict the clinker quality parameters as a function of the raw meal quality and the kiln operating variables. This model has mean squared error, coefficient of determination, worst case relative error and variance account for (in external data) given as 8.96 × 10<sup>–7</sup>, 0.9999, 2.17% and above 97%, respectively. Thus, it is concluded that the developed model can provide real time estimates of the clinker quality parameters and capture wider ranges of real plant operating conditions from first principle-based cement rotary kiln models. Also, the model developed can be utilized online as soft sensor since they contain only variables that are easily measured online. 展开更多
关键词 Clinker quality parameters Online Estimation Cement Rotary Kiln MODEL Soft Sensor
下载PDF
Exploring groundwater quality in semi-arid areas of Algeria:Impacts on potable water supply and agricultural sustainability
12
作者 Noua ALLAOUA Hinda HAFID Haroun CHENCHOUNI 《Journal of Arid Land》 SCIE CSCD 2024年第2期147-167,共21页
Groundwater quality assessment is important to assure safe and durable water use.In semi-arid areas of Algeria,groundwater represents the main water resource for drinking water supply of the rural population as well a... Groundwater quality assessment is important to assure safe and durable water use.In semi-arid areas of Algeria,groundwater represents the main water resource for drinking water supply of the rural population as well as for irrigation of agricultural lands.Groundwater samples from wells and springs were collected from the Gargaat Tarf and Annk Djemel sub-watersheds of the Oum El Bouaghi,Algeria,and were analyzed and compared with the World Health Organization(WHO)standards.Results showed that most of the measured physical and chemical parameters exceeded the quality limits according to the WHO standards.Groundwater had a slightly alkaline water pH(7.00-7.79),electrical conductivity>1500μS/cm,chloride>500 mg/L,calcium>250 mg/L,and magnesium>155 mg/L.Water quality index(WQI)results showed that 68%of the area had excellent water quality,24%of the samples fell into good category,and only 8%were of poor quality and unsuitable for human consumption.Six wells in the area showed bacterial contamination.Total coliforms(453.9(±180.3)CFU(colony-forming units)/100 mL),fecal coliforms(243.2(±99.2)CFU/100 mL),and fecal streptococci(77.9(±32.0)CFU/100 mL)loads were above the standard limits set by the WHO.These results confirmed that water resources in the study area were strongly influenced by anthropogenic activities and were not recommended for consumption as drinking water. 展开更多
关键词 bacteriological indicator GROUNDWATER WATERSHED physical-chemical parameter water quality index
下载PDF
Decreased eggshell strength caused by impairment of uterine calcium transport coincide with higher bone minerals and quality in aged laying hens
13
作者 Yu Fu Jianmin Zhou +4 位作者 Martine Schroyen Haijun Zhang Shugeng Wu Guanghai Qi Jing Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1258-1277,共20页
Background Deteriorations in eggshell and bone quality are major challenges in aged laying hens.This study compared the differences of eggshell quality,bone parameters and their correlations as well as uterine physiol... Background Deteriorations in eggshell and bone quality are major challenges in aged laying hens.This study compared the differences of eggshell quality,bone parameters and their correlations as well as uterine physiologi-cal characteristics and the bone remodeling processes of hens laying eggs of different eggshell breaking strength to explore the mechanism of eggshell and bone quality reduction and their interaction.A total of 24074-week-old Hy-line Brown laying hens were selected and allocated to a high(HBS,44.83±1.31 N)or low(LBS,24.43±0.57 N)eggshell breaking strength group.Results A decreased thickness,weight and weight ratio of eggshells were observed in the LBS,accompanied with ultrastructural deterioration and total Ca reduction.Bone quality was negatively correlated with eggshell quality,marked with enhanced structures and increased components in the LBS.In the LBS,the mammillary knobs and effective layer grew slowly.At the initiation stage of eggshell calcification,a total of 130 differentially expressed genes(DEGs,122 upregulated and 8 downregulated)were identified in the uterus of hens in the LBS relative to those in the HBS.These DEGs were relevant to apoptosis due to the cellular Ca overload.Higher values of p62 protein level,caspase-8 activity,Bax protein expression and lower values of Bcl protein expression and Bcl/Bax ratio were seen in the LBS.TUNEL assay and hematoxylin-eosin staining showed a significant increase in TUNEL-positive cells and tissue damages in the uterus of the LBS.Although few DEGs were identified at the growth stage,similar uterine tissue damages were also observed in the LBS.The expressions of runt-related transcription factor 2 and osteocal-cin were upregulated in humeri of the LBS.Enlarged diameter and more structural damages of endocortical bones and decreased ash were observed in femurs of the HBS.Conclusion The lower eggshell breaking strength may be attributed to a declined Ca transport due to uterine tissue damages,which could affect eggshell calcification and lead to a weak ultrastructure.Impaired uterine Ca transport may result in reduced femoral bone resorption and increased humeral bone formation to maintain a higher mineral and bone quality in the LBS. 展开更多
关键词 Bone parameter Calcium transport Eggshell quality Laying hen Tissue damage
下载PDF
Influence of broken kernels content on soybean quality during storage
14
作者 Lazaro da Costa Correa Canizares Cesar Augusto Gaioso +5 位作者 Newiton da Silva Timm Silvia Leticia Rivero Meza Adriano Hirsch Ramos Maurício de Oliveira Everton Lutz Moacir Cardoso Elias 《Grain & Oil Science and Technology》 CAS 2024年第2期105-112,共8页
Although it is recognized that the post-harvest system is most responsible for the loss of soybean quality,the real impact of this loss is still unknown.Brazilian regulation allows 15%and 30%of broken soybean for grou... Although it is recognized that the post-harvest system is most responsible for the loss of soybean quality,the real impact of this loss is still unknown.Brazilian regulation allows 15%and 30%of broken soybean for group I and group II(quality groups),respectively.However,the industry is not informed about the loss in the quality parameters of soybeans and its impacts during long-term storage.Therefore,the objective was to evaluate the effect of the breakage kernel percentage of soybean stored for 12 months.Content of 15% of breakage kernels did not affect soybean quality.However,content of 30% of breakage kernels affected significantly soybean quality,which was evidenced by the increase of up to 75% in moldy soybeans,72% in acidity,50% in leached solids,27% in electrical conductivity,and the decrease of up to 12% in soluble protein,6.4% in germination and 3.5% in thousand kernel weight after 8 months of storage.Although the legislation establishes a percentage limit,it is recommended to store soybeans with up to 15% breakage kernels.On the contrary,values higher than that can cause a significant reduction in soybean quality,resulting in commercial losses. 展开更多
关键词 Soybean quality Breakage kernels Storage problems Grain defects quality parameters
下载PDF
pharmacognostical study and establishment of quality parameters of aerial parts of Costus speciosus-a well known tropical folklore medicine
15
作者 Pradeep Singh Ratan Lal Khosa +6 位作者 Shruti Srivastava Garima Mishra Keshri Kishor Jha Sourabh Srivastava Sangeeta Ramesh Kumar Verma Mohd Adil Tahseen 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第6期486-491,共6页
Objective:To evaluate the diagnostic pharmacognostical characters of Costus speciosus(aerial parts)along with their physico-chemical parameters and fluorosence analysis.Method:The pharmacognostical characters were det... Objective:To evaluate the diagnostic pharmacognostical characters of Costus speciosus(aerial parts)along with their physico-chemical parameters and fluorosence analysis.Method:The pharmacognostical characters were determined in terms of macroscopy,microscopy,powder microscopy,leaf constant,fluorescence analysis and preliminary phytochemical investigation.Results:The findings of macroscopy revealed that leaves elliptic to oblong or oblong-lancoelate,thick,spirally arranged,with stem clasping sheaths up to 4 cm,flowers large,white,conelike terminal spikes,with bright red bracts.Transverse section of leaflet showed the presence of cuticularised epidermis with polygonal cells on adaxial surface and bluntly angled cells on abaxial surface of lamina,mesophyll cells differentiated in to single layered palisade cells on each surface and 2-3 layered spongy parenchyma,unicellular and uniseriate multicellular covering trichomes,paracytic stomata and vascular bundles surrounded by sclerenchymatous multicellular sheath.Preliminary phytochemical screening exhibited the presence of various phytochemical groups like alkaloids,glycosides,steroids,phenolic constituents.Further,the leaf constants,powder microscopy and fluorescence characteristics indicated outstanding results from this investigation Conclusions:Various pharmacognostical and physico-chemical parameters have pivotal roles in identification,authentication and establishment of quality parameters of the species. 展开更多
关键词 Costus speciosus quality control PHYSICO-CHEMICAL parameters Microscopy Fluorescence analysis
下载PDF
Comparative Study of the Physicochemical Quality of the Waters of the Méné River (Sassandra Watershed, Ivory Coast) in the Dry Season and in the Rainy Season
16
作者 Konan Lopez Kouamé Gansso Valentin Akilinon +2 位作者 Olivier Simon Mananga Kombo Gneneyougo Emile Soro Bi Tié Albert Goula 《Journal of Environmental Protection》 2024年第6期738-746,共9页
The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from ... The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from the river during a period of dry season (January-February) and a period of rainy season (June and September). The various physicochemical parameters were measured according to Afnor standardized methods. The readings of temperature, turbidity, pH and conductivity made it possible to account for the disturbances occurring in water quality. A temporal variation correlated with the seasons (dry or rainy) is noted. Turbidity depends on the concentration of suspended solids (SS) in the water and drained particles and therefore on the seasons. Just like the temperature, the conductivity changes with the season. The waters of the Méné River are generally acidic. The results obtained show that there is a low level of pollution by chlorides, phosphates, nitrites and nitrates. A slight pollution of the waters of Méné in organic matter (chemical oxygen demand values are less than 25 mg∙L−1 during dry season and 32.33 ± 4.73 mg∙L−1 during rainy season) was observed. The concentrations of metallic trace elements such as iron, manganese and aluminum indicate significant pollution of these waters by these elements. Overall, the waters of the Méné River are of satisfactory quality because all the physicochemical parameters analyzed have values below standards during the dry season as well as during the rainy season with the exception of COD and a few metallic trace elements. 展开更多
关键词 Méné Physicochemical parameters RIVER SEASON Water quality
下载PDF
PARAMETER ESTIMATION OF MULTI-CONSTITUENT WATER QUALITY MODEL FOR THE LIANGXI RIVER BY MARQUARDT METHOD
17
作者 Liu Shuxia(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z1期110-118,共9页
A multi-constituent water quality model is presented,Which relates carbonaceous biochemical oxygen demand (CBOD),amonia (NH3-N), nitrite(NO2-N), nitrate(NO3-N) and dissolvedoxygen(DO). The parameters are solved by Mar... A multi-constituent water quality model is presented,Which relates carbonaceous biochemical oxygen demand (CBOD),amonia (NH3-N), nitrite(NO2-N), nitrate(NO3-N) and dissolvedoxygen(DO). The parameters are solved by Marquardt Method (i. e.,Dampled Least Square Method) while initial values inoptimization are produced by Monte-Carlo Method. The Potential ofthe method as a parameter estimation aid is demonstrated for theapplication to the Liangyi Rver, JiangSu Province of China and by aspecial comparison with Gauss Method. 展开更多
关键词 nitrogen pollution water quality model parameter estimation Marquardt Method Monte-Carlo Method
下载PDF
Cookie Baking Process Optimization and Quality Analysis Based on Food 3D Printing
18
作者 Liu Chenghai Li Jingyi +2 位作者 Wu Chunsheng Zhao Xinglong Zheng Xianzhe 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期61-73,共13页
In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the in... In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the influences of baking process parameters, such as baking time, surface heating temperature and bottom heating temperature, on the quality of the cookie were studied to optimize the baking process parameters. The results showed that the baking process parameters had obvious effects on the texture, color, deformation, moisture content, and temperature of the cookie. All of the roasting surface heating temperature, bottom heating temperature and baking time had positive influences on the hardness, crunchiness, crispiness, and the total color difference(ΔE) of the cookie. When the heating temperatures of the surfac and bottom increased, the diameter and thickness deformation rate of the cookie increased. However,with the extension of baking time, the diameter and thickness deformation rate of the cookie first increased and then decreased. With the surface heating temperature of 180 ℃, the bottom heating temperature of 150 ℃, and baking time of 15 min, the cookie was crisp and moderate with moderate deformation and uniform color. There was no burnt phenomenon with the desired quality. Research results provided a theoretical basis for cookie manufactory based on food 3D printing technology. 展开更多
关键词 food 3D printing baking process COOKIE quality analysis optimization of process parameter
下载PDF
Evaluation of Quality Parameters of White and Brown Eggs in Lebanon
19
作者 Karine Joubrane Dima Mnayer +3 位作者 Tayssir Hamieh Georges Barbour Rabih Talhouk Elie Awad 《American Journal of Analytical Chemistry》 2019年第10期488-503,共16页
The quality traits of fresh marketable chicken eggs collected during winter, autumn and summer periods from different local markets in Lebanon were evaluated in order to understand the reproductive fitness of the chic... The quality traits of fresh marketable chicken eggs collected during winter, autumn and summer periods from different local markets in Lebanon were evaluated in order to understand the reproductive fitness of the chicken and the correlation between collection dates. A total of 2000 brown and white eggs were analyzed and compared for their external quality parameters such as egg weight, length, width, size, shell thickness, specific gravity and for their internal quality traits such as Haugh unit, yolk diameter, yolk color, and yolk height. Results show that egg weight and size varied markedly and tended to be smaller during summer period. A significant difference was found between white and brown eggs in some quality traits such as egg weight, shell thickness, egg length, and yolk diameter parameters. Egg quality parameters were significantly reduced during summer season where eggs are exposed to high temperature conditions. For grading analysis, 80% of the total eggs were classified as A with a significant difference (p < 0.05) between white and brown egg and during collection dates. Overall, brown eggs graded better than white eggs in external quality cleanliness and shape. Based on our analysis, the results of this study show that Lebanese eggs are of good quality and suggest that proper egg handling and storage conditions should be applied especially at warm environmental conditions to improve egg quality during summer season. 展开更多
关键词 BROWN and WHITE EGGS EGG quality Control quality parameterS
下载PDF
No-Reference Image Quality Assessment Method Based on Visual Parameters
20
作者 Yu-Hong Liu Kai-Fu Yang Hong-Mei Yan 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第2期171-184,共14页
Recent studies on no-reference image quality assessment (NR-IQA) methods usually learn to evaluate the image quality by regressing from human subjective scores of the training samples. This study presented an NR-IQA m... Recent studies on no-reference image quality assessment (NR-IQA) methods usually learn to evaluate the image quality by regressing from human subjective scores of the training samples. This study presented an NR-IQA method based on the basic image visual parameters without using human scored image databases in learning. We demonstrated that these features comprised the most basic characteristics for constructing an image and influencing the visual quality of an image. In this paper, the definitions, computational method, and relationships among these visual metrics were described. We subsequently proposed a no-reference assessment function, which was referred to as a visual parameter measurement index (VPMI), based on the integration of these visual metrics to assess image quality. It is established that the maximum of VPMI corresponds to the best quality of the color image. We verified this method using the popular assessment database—image quality assessment database (LIVE), and the results indicated that the proposed method matched better with the subjective assessment of human vision. Compared with other image quality assessment models, it is highly competitive. VPMI has low computational complexity, which makes it promising to implement in real-time image assessment systems. 展开更多
关键词 BANDWIDTH human VISUAL system information entropy LUMINANCE NO-REFERENCE image quality assessment (NR-IQA) VISUAL parameter measurement index (VPMI)
下载PDF
上一页 1 2 177 下一页 到第
使用帮助 返回顶部