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1.
Micromachines (Basel) ; 14(6)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37374704

RESUMEN

Integrated circuit (IC) X-ray wire bonding image inspections are crucial for ensuring the quality of packaged products. However, detecting defects in IC chips can be challenging due to the slow defect detection speed and the high energy consumption of the available models. In this paper, we propose a new convolutional neural network (CNN)-based framework for detecting wire bonding defects in IC chip images. This framework incorporates a Spatial Convolution Attention (SCA) module to integrate multi-scale features and assign adaptive weights to each feature source. We also designed a lightweight network, called the Light and Mobile Network (LMNet), using the SCA module to enhance the framework's practicality in the industry. The experimental results demonstrate that the LMNet achieves a satisfactory balance between performance and consumption. Specifically, the network achieved a mean average precision (mAP50) of 99.2, with 1.5 giga floating-point operations (GFLOPs) and 108.7 frames per second (FPS), in wire bonding defect detection.

2.
Artículo en Inglés | MEDLINE | ID: mdl-35627661

RESUMEN

Since the COVID-19 epidemic outbreak at the end of 2019, many studies regarding the impact of meteorological factors on the attack have been carried out, and inconsistent conclusions have been reached, indicating the issue's complexity. To more accurately identify the effects and patterns of meteorological factors on the epidemic, we used a combination of logistic regression (LgR) and partial least squares regression (PLSR) modeling to investigate the possible effects of common meteorological factors, including air temperature, relative humidity, wind speed, and surface pressure, on the transmission of the COVID-19 epidemic. Our analysis shows that: (1) Different countries and regions show spatial heterogeneity in the number of diagnosed patients of the epidemic, but this can be roughly classified into three types: "continuous growth", "staged shock", and "finished"; (2) Air temperature is the most significant meteorological factor influencing the transmission of the COVID-19 epidemic. Except for a few areas, regional air temperature changes and the transmission of the epidemic show a significant positive correlation, i.e., an increase in air temperature is conducive to the spread of the epidemic; (3) In different countries and regions studied, wind speed, relative humidity, and surface pressure show inconsistent correlation (and significance) with the number of diagnosed cases but show some regularity.


Asunto(s)
COVID-19 , Epidemias , COVID-19/epidemiología , Humanos , Conceptos Meteorológicos , Meteorología , Viento
3.
Se Pu ; 25(5): 743-6, 2007 Sep.
Artículo en Chino | MEDLINE | ID: mdl-18161331

RESUMEN

A method for the simultaneous determination of seven sulfonamides (sulfacetamide, sulfapyridine, sulfamerazine, sulfamethazine, sulfamater, sulfamonomethoxine, sulfamethoxazole) and metronidazole, chloramphenicol in cosmetics has been developed by high performance liquid chromatography with a photodiode array detector (HPLC-PDA). The chromatographic column Atlantis dC18 (150 mm x 4.6 mm, 5 microm) was used with acetonitrile-0.1% formic acid (2:8, v/v) aqueous solution as mobile phase at a flow rate of 1.0 mL/min. Samples were extracted by mobile phase and detected by HPLC-PDA at 268 nm. The limits of quantification were 3 - 80 microg/g. The correlation coefficients of linear calibration curves were over 0. 999 3 within the sulfonamide concentration range of 20 - 200 microg/mL and metronidazole and chloramphenicol concentration range of 40 - 400 microg/mL. Average recoveries were 83.8% - 105.3% at the spiked levels of 50 microg/mL and 150 microg/mL for sulfonamides, and 100 microg/mL and 300 microg/mL for metronidazole and chloramphenicol. The relative standard deviations were below 5%. This method can be routinely used for the determination of seven sulfonamides and metronidazole, chloramphenicol in cosmetics.


Asunto(s)
Cloranfenicol/análisis , Cromatografía Líquida de Alta Presión/métodos , Cosméticos/química , Metronidazol/análisis , Sulfonamidas/análisis , Reproducibilidad de los Resultados
4.
Se Pu ; 25(2): 238-40, 2007 Mar.
Artículo en Chino | MEDLINE | ID: mdl-17580695

RESUMEN

A method for the determination of 12 sulfonamides (SAs) (sulfanilamide, sulfamonomethoxine, sulfacetamide, sulfamethoxazole, sulfadiazine, sulfisoxazole, sulfathiazole, sulfadi-methoxine, sulfamerazine, sulfaquinoxaline, sulfamethazine, sulfanitran) in cosmetics was developed by ultra performance liquid chromatography with photodiode array detector (UPLC-PDA). The chromatographic column used was Acquity UPLC BEHC C18 (50 mm x 2. 1 mm, 1. 7 microm) and the mobile phase was acetonitrile-0. 1% formic acid aqueous solution. A gradient elution program was utilized for the separation and determination. After liquid-liquid extraction, SAs were separated and detected by UPLC-PDA. The qualification analysis was done by using retention time and spectrum, and the quantification was based on the detection wavelength of 268 nm. The limits of qualification (S/N = 3) and quantification (S/N = 10) for 12 SAs were 1 microg/g and 2 -3 microg/g, respectively. The correlation coefficient of linear calibration curve was over 0. 999 7 within the SAs concentration range of 1 - 25 mg/L (except sulfanitran 0. 5 - 12. 5 mg/L). At the spiked levels of 40 and 8 microg (except sulfanitran 20 and 4 microg), the average recoveries for 12 SAs were 86. 8% - 98. 1% and 80. 1% - 96. 9%, respectively. Relative standard deviations were less than 10%. Routine tests show that the method is simple, fast, and has a good separation efficiency. It can be routinely used for the determination of these SAs in cosmetics.


Asunto(s)
Cromatografía Liquida/métodos , Sulfonamidas/análisis , Cosméticos/análisis , Reproducibilidad de los Resultados , Sulfacetamida/análisis , Sulfadiazina/análisis , Sulfamerazina/análisis , Sulfametazina/análisis , Sulfametoxazol/análisis , Sulfamonometoxina/análisis , Sulfanilamida , Sulfanilamidas/análisis , Sulfaquinoxalina/análisis , Sulfatiazol , Sulfatiazoles/análisis , Sulfisoxazol/análisis
5.
Wei Sheng Yan Jiu ; 36(1): 75-7, 2007 Jan.
Artículo en Chino | MEDLINE | ID: mdl-17424856

RESUMEN

OBJECTIVE: In order to survey water eutrophication and microcystin levels in Beijing Miyun Reservoir. METHODS: Mivrocystin-LR (MC-LR), and MC-RR were determinated by LC/MS/MS at 5 sample sites in Miyun Reservoir. Eutrophication parameters, which were determinated by conventional analytical methods, included algae number, chlorophyll-a (Chl-a), total phosphor (TP), total nitrogen (TN), COD,TOC, Fe, turbidity and water temperature. RESULTS: Water in Miyun Reservoir was polluted very little by organic matter. According to Chl-a, TP appraise criterion and grading method, Miyun Reservoir was eutrophicated very little. MC-LR and MC-RR could be detected out in water of Miyun Reservoir. Maximum concentration was discovered in September, MC-LR 41 ng/L and MC-RR 18 ng/L respectively. CONCLUSION: Beijing Miyun Reservoir was poor-eutrophic. Microcystins concentration in water of Miyun Reservoir was far lower than our country health standard.


Asunto(s)
Monitoreo del Ambiente , Eutrofización , Microcistinas/análisis , Contaminantes del Agua/análisis , Abastecimiento de Agua , China
6.
Environ Technol ; 25(7): 757-61, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15346856

RESUMEN

This study shows diethyl phthalate (DEP) and dibutyl phthalate (DBP) were substantially adsorbed by activated sludge and its extracellular polymeric substance (EPS). The adsorption characteristics followed Freundlich and Langmuir isotherms. According to the Langmuir isotherm, each gram of activated sludge at maximum adsorbed 0.73 mg of DEP and 17.6 mg of DBP, and each gram of centrifugation-extracted EPS adsorbed 14.3 mg of DEP and 10.6 mg of DBP. The adsorption increased with the hydrophobicity of phthalates. This suggests most phthalates, which are of higher hydrophobicity than DEP and DBP, are likely to be removed from wastewater through adsorption by the activated sludge in the biological treatment process.


Asunto(s)
Reactores Biológicos , Modelos Teóricos , Ácidos Ftálicos/química , Ácidos Ftálicos/aislamiento & purificación , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Adsorción , Biopolímeros , Temperatura
7.
J Environ Sci (China) ; 15(6): 783-90, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14758897

RESUMEN

The sunlight photodegradation half-lives of 20 mg/L acetochlor were 151, 154 and 169 days in de-ionized water, river water and paddy water, respectively. When exposed to ultraviolet (UV) light, acetochlor in aqueous solution was rapidly degraded. The half-lives were 7.1, 10.1, and 11.5 min in de-ionized water, river water and paddy water, respectively. Photoproducts of acetochlor were identified by gas chromatography/mass spectrometry (GC/MS) and found at least twelve photoproducts resulted from dechlorination with subsequent hydroxylation and cyclization processes. The chemical structures of ten photoproducts were presumed on the basis of mass spectrum interpretation and literature data. Photoproducts are identified as 2-ethyl-6-methylaniline; N,N-diethylaniline; 4,8-dimethyl-2-oxo-1,2,3,4-tetrahydroquinoline; 2-oxo-N-(2-ethyl-6-methylphenyl)-N-(ethoxymethyl) acetamide; N-(ethoxymethyl)-2'-ethyl-6'-methylformanilide; 1-hydroxyacetyl-2-ethoxyl-7-ethylindole; 8-ethyl-1-ethoxymethyl-2-oxo-1,2,3,4-tetrahydroquinoline; 4, 8-dimethyl-1-ethoxymethyl-2-oxo-1,2,3,4-tetrahydroquinoline; 2-hydroxy-2'-ethyl-6'-methyl-N-(ethoxymethyl) acetanilide and a compound related to acetochlor. The other two photoproducts were detected by GC/MS although their chemical structure was unknown.


Asunto(s)
Herbicidas/química , Fotoquímica , Toluidinas/química , Rayos Ultravioleta , Agua/química , China , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Cinética
8.
J Environ Sci (China) ; 14(4): 524-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12491727

RESUMEN

The biodegradation of two acetanilide herbicides, acetochlor and butachlor in soil after other environmental organic matter addition were measured during 35 days laboratory incubations. The herbicides were applied to soil alone, soil-SDBS (sodium dodecylbenzene sulfonate) mixtures and soil-HA (humic acid) mixtures. Herbicide biodegradation kinetics were compared in the different treatment. Biodegradation products of herbicides in soil alone samples were identified by GC/MS at the end of incubation. Addition of SDBS and HA to soil decreased acetochlor biodegradation, but increased butachlor biodegradation. The biodegradation half-life of acetochlor and butachlor in soil alone, soil-SDBS mixtures and soil-HA mixtures were 4.6 d, 6.1 d and 5.4 d and 5.3 d, 4.9 d and 5.3 d respectively. The biodegradation products were hydroxyacetochlor and 2-methyl-6-ethylaniline for acetochlor, and hydroxybutachlor and 2,6-diethylaniline for butachlor.


Asunto(s)
Acetanilidas/metabolismo , Herbicidas/metabolismo , Microbiología del Suelo , Toluidinas/metabolismo , Bencenosulfonatos/metabolismo , Biodegradación Ambiental , Semivida , Sustancias Húmicas/metabolismo , Cinética
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