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Electron G-Factor Anomaly and the Charge Thickness
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作者 Arlen Young 《Journal of Modern Physics》 2024年第4期435-447,共13页
The electron g-factor relates the magnetic moment to the spin angular momentum. It was originally theoretically calculated to have a value of exactly 2. Experiments yielded a value of 2 plus a very small fraction, ref... The electron g-factor relates the magnetic moment to the spin angular momentum. It was originally theoretically calculated to have a value of exactly 2. Experiments yielded a value of 2 plus a very small fraction, referred to as the g-factor anomaly. This anomaly has been calculated theoretically as a power series of the fine structure constant. This document shows that the anomaly is the result of the electron charge thickness. If the thickness were to be zero, g = 2 exactly, and there would be no anomaly. As the thickness increases, the anomaly increases. An equation relating the g-factor and the surface charge thickness is presented. The thickness is calculated to be 0.23% of the electron radius. The cause of the anomaly is very clear, but why is the charge thickness greater than zero? Using the model of the interior structure of the electron previously proposed by the author, it is shown that the non-zero thickness, and thus the g-factor anomaly, are due to the proposed positive charge at the electron center and compressibility of the electron material. The author’s previous publication proposes a theory for splitting the electron into three equal charges when subjected to a strong external magnetic field. That theory is revised in this document, and the result is an error reduced to 0.4% in the polar angle where the splits occur and a reduced magnetic field required to cause the splits. 展开更多
关键词 Electron G-Factor Anomaly Electron Charge thickness Electron Positive Charge Electron Mass thickness Electron Fractionalization Splitting the Electron Electron Compressibility Factor
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Absolute Wall Thickness Measurement of Conducting Plates Using Pulsed Eddy Currents
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作者 Victor-O. de Haan Riccardo Scottini 《Journal of Electromagnetic Analysis and Applications》 2024年第3期25-41,共17页
The method using pulsed eddy currents to determine the thickness of a conduction plate is extended to enable the simultaneous measurement of the plate thickness and material properties. For optimal performance, a prob... The method using pulsed eddy currents to determine the thickness of a conduction plate is extended to enable the simultaneous measurement of the plate thickness and material properties. For optimal performance, a probe must be designed depending on the thickness range that should be accessible. The need for a calibration of the material properties of a conducting plate to enable the measurement of its thickness has been removed. All that is needed is a probe with known dimensions and suitable hardware to create a current pulse and measure a transient magnetic induction. 展开更多
关键词 Pulsed Eddy Currents Wall thickness Absolute and Relative Measurements
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Comparative Analysis of Statistical Thickness Models for the Determination of the External Specific Surface and the Surface of the Micropores of Materials: The Case of a Clay Concrete Stabilized Using Sugar Cane Molasses
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作者 Nice Mfoutou Ngouallat Narcisse Malanda +3 位作者 Christ Ariel Ceti Malanda Kris Berjovie Maniongui Erman Eloge Nzaba Madila Paul Louzolo-Kimbembe 《Geomaterials》 2024年第2期13-28,共16页
In this work, four empirical models of statistical thickness, namely the models of Harkins and Jura, Hasley, Carbon Black and Jaroniec, were compared in order to determine the textural properties (external surface and... In this work, four empirical models of statistical thickness, namely the models of Harkins and Jura, Hasley, Carbon Black and Jaroniec, were compared in order to determine the textural properties (external surface and surface of micropores) of a clay concrete without molasses and clay concretes stabilized with 8%, 12% and 16% molasses. The results obtained show that Hasley’s model can be used to obtain the external surfaces. However, it does not allow the surface of the micropores to be obtained, and is not suitable for the case of simple clay concrete (without molasses) and for clay concretes stabilized with molasses. The Carbon Black, Jaroniec and Harkins and Jura models can be used for clay concrete and stabilized clay concrete. However, the Carbon Black model is the most relevant for clay concrete and the Harkins and Jura model is for molasses-stabilized clay concrete. These last two models augur well for future research. 展开更多
关键词 Statistical thickness Model External Specific Surface Microporous Surface Clay Concrete MOLASSES
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Determination of the Series Resistance of a Series Vertical-Junction Silicon (N+/P/P+) Solar Cell under Polychromatic Illumination and Magnetic Field: Effect of Optimum Thickness
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作者 Dibor Faye Babou Dione +1 位作者 Mountaga Boiro Pape Diop 《Journal of Modern Physics》 2024年第10期1543-1554,共12页
By solving the magneto-transport equation for excess minority charge carriers in the base of the series vertical-junction silicon cell, the phenomenological parameters of the cell can be determined from the boundary c... By solving the magneto-transport equation for excess minority charge carriers in the base of the series vertical-junction silicon cell, the phenomenological parameters of the cell can be determined from the boundary conditions. Photocurrent density and photovoltage are determined for each value of applied magnetic field and corresponding optimum thickness, to establish the current-voltage characteristic (Jph(Sf, Sb, z, B, Hop)-Vph(Sf, Sb, z, B, Hop) of the silicon cell under polychromatic illumination. This study will make it possible to reduce the material used (by reducing the optimum thickness), which will help to lower prices. It will also enable us to reduce betting effects (lower series resistance), thereby boosting solar cell efficiency. 展开更多
关键词 Series Vertical Junction Silicon Cell Static Regime Magnetic Field Optimum thickness Series Resistance
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Analysis of the Risk of Water Breakout in the Bottom Plate of High-Intensity Mining of Extra-Thick Coal Seams
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作者 Shuo Wang Hongdong Kang Xinchen Wang 《Journal of Geoscience and Environment Protection》 2024年第5期81-91,共11页
In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site moni... In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site monitoring means combining borehole peeping and microseismic monitoring, combined with the theoretical analysis to analyze the danger of water breakout in the bottom plate. The results show that: 1) the theoretically calculated maximum damage depth of the bottom plate is 27.5 m, and its layer is located above the Austrian ash aquifer, which has the danger of water breakout;2) the drill hole peeping at the bottom plate of the working face shows that the depth of the bottom plate fissure development reaches 26 m, and the integrity of the water barrier layer has been damaged, so there is the risk of water breakout;3) for the microseismic monitoring of the anomalous area, the bottom plate of the return air downstream channel occurs in the field with a one-week lag, which shows that microseismic monitoring events may reflect the water breakout of the underground. This shows that the microseismic monitoring events can reflect the changes of the underground flow field, which can provide a reference basis for the early warning of water breakout. The research results can provide reference for the prediction of sudden water hazard. 展开更多
关键词 Extra-thick Coal Seam High-Intensity Mining Microseismic Monitoring Water-Surge Hazard Borehole Peeping
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Evaluating Residual Dentine Thickness Cervically Following Various Anterior Crown Preparations for Zirconia Full Coverage Single Crowns: An in Vitro Analysis
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作者 Nana Frimpomah Adu-Ampomah Patrick Caldicock Ampofo +5 位作者 Anno Nyako Sandra Hewlett Alexander Oti Acheampong Gladia Toledo Mayari Yabang Ruby Goka Stephen Ankoh 《Open Journal of Stomatology》 2023年第11期403-413,共11页
Background: A reduced residual dentine thickness following crown preparation has a conceivable impact on pulp degeneration by increasing the pulp’s susceptibility to injury. In crown preparations, three different fin... Background: A reduced residual dentine thickness following crown preparation has a conceivable impact on pulp degeneration by increasing the pulp’s susceptibility to injury. In crown preparations, three different finishing lines are used. These are shoulder, chamfer, and knife edge. Each with its comparative advantages and disadvantages. There is inadequate scientific evidence on which of these finishing lines will leave the most amount of residual dentine, after standard crown preparations on mandibular incisors and maxillary lateral incisors to preserve their pulpal health. Objective: To evaluate residual dentine thickness following various cervical finishing lines of anterior crown preparations for zirconia full coverage. Materials and Methods: A prospective comparative study was conducted from September 2<sup>nd</sup> to November 5<sup>th</sup>, 2022, using mandibular incisors and maxillary laterals extracted from individuals between ages 18 to 30. Each of the three groups of teeth was randomly divided into three cervical margin preparations as follows: Shoulder (n = 15), chamfer (n = 15), and knife edge (n = 15). The teeth were disinfected and stored in 10% formalin. Silicone impressions followed by crown preparations were done on teeth mounted on phantom head manikins. The teeth were sectioned 0.5 mm coronal to the cemento-enamel junction using a separating disc and the mesial, distal, buccal, and lingual thickness were measured using a digital caliper. ANOVA analysis was applied to assess the difference in mean residual dentine thickness among the finishing lines and the Tukey test used for mean comparison. Results: Knife edge finishing lines had 2.05 mm of residual dentine thickness, for upper lateral incisors lingually and had an amount of 1.55 mm and 1.47 mm for lower central teeth mesially and distally respectively. Shoulder finishing lines had an amount of 0.58 mm for lower lateral incisors mesially. Interproximal areas had the least amounts of residual dentine for shoulder and chamfer finishing lines of 0.58 mm and 0.78 mm respectively. Conclusions: There was a significant statistical difference in the thickness of residual dentine at the various cervical finishing line margins. The knife edge finishing line was protective enough for zirconia crown preparations. 展开更多
关键词 RESIDUAL Dentine thickness CERVICAL Finishing Margins
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An in Vitro Analysis to Evaluate Coronal Residual Dentine Thickness after Different Anterior Crown Preparations
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作者 Nana Frimpomah Adu-Ampomah Patrick Caldicock Ampofo +5 位作者 Anno Nyako Sandra Hewlett Alexander Oti Acheampong Gladia Toledo Mayari Yabang Stephen Ankoh Ruby Goka 《Open Journal of Stomatology》 2023年第12期442-449,共8页
Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists re... Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists regarding which of these finishing lines will leave the most amount of residual dentine coronally on maxillary lateral incisors and mandibular incisors. Objective: To assess the coronal residual dentine thickness after different cervical finishing lines for anterior crown preparations. Materials and Methods: A prospective comparative study was conducted including mandibular incisors and maxillary laterals that were taken from subjects from 18 to 30 years old. Teeth in each of the three groups were randomly separated into three cervical margin preparation groups: knife edge, chamfer and shoulder. The teeth were then prepared for single crown coverage using these finishing lines. The teeth were sectioned halfway through the crown preparation, and a digital caliper was used to determine the residual dentine thickness at the buccal, lingual, mesial and distal areas. The Tukey test was used for mean comparison, and ANOVA analysis was used to evaluate the variation in mean residual dentine thickness. Results: For upper lateral incisors, knife edge finishing lines showed the highest amount of remaining dentine thickness—1.5 mm. lingually, while the upper lateral incisors mesially had the least amount of 0.53 mm for shoulder finishing lines. The least residual dentine (0.53 mm for the shoulder and 0.70 mm for the chamfer finishing line) was found in the interproximal portions of all the teeth that were selected. Lower central incisors had the least amount of residual dentine 0.61 mm for shoulder preparations mesially whiles lower lateral incisors had the least amount of residual dentine for shoulder preparations 0.58 mm distally. There was a statistically significant difference of 0.001 across the groups. Conclusion: The thickness of residual dentine seen coronally after the three finishing line preparations showed a statistically significant difference and the knife edge finishing line provided enough coronal protection within the scope of this study. 展开更多
关键词 CORONAL Finishing Lines Residual Dentine thickness
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Short Term Effect of 0.02%/0.04% Atropine Sulfate Eye Drops on Choroid Thickness in Children with Myopia
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作者 Xinwen Zhang 《Journal of Biosciences and Medicines》 2023年第8期1-17,共17页
Objective: Short-term effects of 0.02%/0.04% atropine sulfate eye drops on choroidal thickness in myopic children using optical coherence tomography angiography. Methods: Thirty-two children aged 6 - 12 years were sel... Objective: Short-term effects of 0.02%/0.04% atropine sulfate eye drops on choroidal thickness in myopic children using optical coherence tomography angiography. Methods: Thirty-two children aged 6 - 12 years were selected and divided into 22 cases and 44 eyes in the 0.02%/0.04% atropine sulfate eye drops observation group and 10 cases and 20 eyes in the control group. The linear regression equation was used to evaluate the correlation among the spherical equivalent, the axial length and the subfoveal choroidal thickness, moreover, used to evaluate the correlation between the baseline and 6 months later. Independent samples T-test was used to detect whether there was any statistical difference between the nasal 1 mm subfoveal choroidal thickness and the temporal 1 mm subfoveal choroidal, meanwhile, compared with the baseline and 6 months later. P Results: After 6 months follow-up, the axial length increased by 0.067 ± 0.199 mm in the atropine group, 0.201 ± 0.081 mm in the control group (P Conclusions: 1) 0.02%/0.04% atropine sulfate eye drops can delay the growth of axial length and spherical equivalent;2) 0.02%/0.04% atropine sulfate eye drops can thicken the choroid, and the thickness of the nasal side 1mm is the same as that of the temporal side 1 mm;3) At baseline, the subfoveal choroidal thickness has no significant correlation with the axial length and spherical equivalent;4) After 6 months, changes in axial length and spherical equivalent were negatively correlated with changes in subfoveal choroidal thickness. 展开更多
关键词 MYOPIA ATROPINE Optical Coherence Tomography Angiography Choroid thickness
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Determination of the Base Optimum Thickness of Back Illuminated (n+/p/p+) Bifacial Silicon Solar Cell, by Help of Diffusion Coefficient at Resonance Frequency
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作者 Mohamed Yaya Teya Ousmane Sow +5 位作者 Khady Loum Ibrahima Diatta Gora Diop Youssou Traore Mamadou Wade Gregoire Sissoko 《Journal of Electromagnetic Analysis and Applications》 CAS 2023年第2期13-24,共12页
The bifacial silicon solar cell subjected to a magnetic field, is illuminated by the back side by a monochromatic light in frequency modulation, with high absorption, At minority carriers diffusion coefficient resonan... The bifacial silicon solar cell subjected to a magnetic field, is illuminated by the back side by a monochromatic light in frequency modulation, with high absorption, At minority carriers diffusion coefficient resonance frequency, a graphical study of the expressions of recombination velocity on the rear side is carried out. The optimum thickness of the base of the bifacial solar cell is deduced for each resonance frequency. 展开更多
关键词 Bifacial Silicon Solar Cell Frequency Magnetic Field Wavelength-Recombination Velocity Base thickness
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The Mean Central Cornea Thickness and Associated Factors among Adult Patients Attending Mulago Hospital Eye Clinic Kampala, Uganda
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作者 Samia Hersi Ali Anne Ampaire Musika +3 位作者 Immaculate Atukunda Rebecca Claire Lusobya John Mukisa Edward Nkurunziza 《Open Journal of Ophthalmology》 2023年第2期221-232,共12页
Background: The mean central corneal thickness (CCT) values are known to have an influence on intraocular pressure measurement and vary widely with age, sex and ethnicity. Little is known about the pattern of CCT in c... Background: The mean central corneal thickness (CCT) values are known to have an influence on intraocular pressure measurement and vary widely with age, sex and ethnicity. Little is known about the pattern of CCT in central Uganda. Aim: To determine the mean central corneal thickness and its associated factors among adult patients attending Mulago Hospital eye clinic, Kampala Uganda. Design and Method: A cross sectional study was done from August to October 2016 on 270 adult patients selected by systemic random sampling. The study included all adult patients who attended the eye clinic during the study period and consented to the study excluding those who had conditions causing abnormal thinning, thickening or irregularity of the cornea. The participants were evaluated by history taking and ocular examination including visual acuity assessment, slit lamp examination, central cornea thickness measurement, intraocular pressure measurement and funduscopy. Data were collected using a pretested questionnaire, entered using Epidata and analyzed by STATA11.0. Results: Of the 270 patients examined, 61% were female, 39% male, the mean age being 42 years ranging from 18 to 96 years. The mean central corneal thickness for both eyes was 539.3 (SD ± 41.65 μm) ranging from 332 μm to 701 μm and mean intraocular pressure was 15 (SD ± 5.34) mmHg. Gender, ethnicity, IOP, glaucoma, hypertension, diabetes, refractive error, were not statistically significantly associated with central cornea thickness. However central cornea thickness was statistically significantly associated with systolic blood pressure (r = -0.24, p = 0.025) and age (p = 0.002). A one-year increase in age reduced the mean central cornea thickness by 0.54 μm. Conclusion: The average CCT of Ugandan adult population was 539.3 ± 41.65 μm which falls in the category of normal central cornea thickness. Central corneal thickness reduced with increasing age and increasing systolic blood pressure. 展开更多
关键词 Central Cornea thickness Intraocular Pressure FUNDUS
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Accuracy of Trans-Cerebellar Diameter and Placental Thickness in Third Trimesteric Pregnant Women for Calculation of Gestational Age: A Cross Sectional Study
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作者 Alaa Sayed Hassanin Hassan Tawfik Khairy +1 位作者 Aya Tullah Abd Elfatah Elshaer Sarah Safwat 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期303-314,共12页
Background: Accurate determination of gestational age has become important for deciding the appropriate time for termination of the pregnancy as well as to monitor the fetal growth during the entire period of pregnanc... Background: Accurate determination of gestational age has become important for deciding the appropriate time for termination of the pregnancy as well as to monitor the fetal growth during the entire period of pregnancy. Objective: The aim of the study was to assess whether the trans-cerebellar diameter, placental thickness or combining both of them is more accurate for assessment of gestational age in the 3<sup>rd</sup> trimester of pregnancy. Patients and Methods: This is a cross sectional study conducted at outpatient Clinic and Obstetric ward, Ain Shams University Maternity Hospital, over a period of six months from March 2019 to September 2019. One hundred pregnant women were recruited according to inclusion criteria either from outpatient clinic or were admitted in obstetric ward Ain Shams Maternity Hospital to find out the most accurate fetal biometric measurement in the third trimester either trans-cerebellar diameter placental thickness or both compared to reliable LMP (last menstrual period) dates confirmed by crown rump length (CRL) in the first trimester. Results: Trans-cerebellar diameter mean ± SD was 46.0 ± 3.5 with range 38.2 - 51.7. The mean of placental thickness was 39.6 ± 7.1 with range 22.8 - 54.3. Placental thickness had highest determination (0.813) for last menstrual period followed by trans-cerebellar diameter (0.802). Combining trans-cerebellar diameter and placental thickness increased determination (0.902) for last menstrual period. Conclusion: Combined use of trans-cerebellar diameter and placental thickness in the third trimester of pregnancy is a reliable indicator for gestational age in women whose last menstrual period is unreliable or unknown, but placental thickness had higher accuracy than trans-cerebellar diameter. 展开更多
关键词 Accuracy of Trans-Cerebellar Diameter Placental thickness Third Tri-mesteric Pregnant Women Gestational Age
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Central Corneal Thickness of Diabetic Patients in Yaoundé: Case Control Study
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作者 Chantal Nanfack Ngoune Marie Evodie Akono Zoua +4 位作者 Arlette Nomo Christelle Noëlle Nganso Nankep Mesmin Dehayem Christelle Noche Domngang Giles Kagmeni 《Open Journal of Ophthalmology》 2023年第1期136-142,共7页
Background: To compare central corneal thickness (CCT) values measured in diabetic eyes and compare the CCT values in normal patients without diabetes. Methods: A total of 83 diabetic patients and 83 non-diabetic pati... Background: To compare central corneal thickness (CCT) values measured in diabetic eyes and compare the CCT values in normal patients without diabetes. Methods: A total of 83 diabetic patients and 83 non-diabetic patients were prospectively enrolled in this comparative case series. CCT was measured using a Topcon CT-1P non-contact automated pachymeter, and values were compared. Results: Mean age was 57 ± 11 years, with a range of 23 and 80 years. The mean CCT was 508.87 ± 35.83 μm for diabetic patients and 513.41 ± 37.22 μm for non-diabetic patients. There was no statistically significant difference between the CCT of diabetic patients compared to non-diabetic patients (p = 0.260). We did not find a significant correlation between the CCT of diabetic patients and clinical characteristics of diabetes. However, there was a positive and statistically significant linear correlation between the CCT of diabetic patients and intra ocular pressure (IOP). Conclusion: The mean CCT in diabetic patients was lower than in non-diabetic control patients, although there was no statistically significant difference. 展开更多
关键词 Cornea Central thickness Diabetic Retinopathy DIABETES Intra Ocular Pres-sure
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AC Back Surface Recombination Velocity as Applied to Optimize the Base Thickness under Temperature of an (n+-p-p+) Bifacial Silicon Solar Cell, Back Illuminated by a Light with Long Wavelength
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作者 Khady Loum Ousmane Sow +7 位作者 Gora Diop Richard Mane Ibrahima Diatta Malick Ndiaye Sega Gueye Moustapha Thiame Mamadou Wade Gregoire Sissoko 《World Journal of Condensed Matter Physics》 CAS 2023年第1期40-56,共17页
The bifacial silicon solar cell, placed at temperature (T) and illuminated from the back side by monochromatic light in frequency modulation (ω), is studied from the frequency dynamic diffusion equation, relative to ... The bifacial silicon solar cell, placed at temperature (T) and illuminated from the back side by monochromatic light in frequency modulation (ω), is studied from the frequency dynamic diffusion equation, relative to the density of excess minority carriers in the base. The expressions of the dynamic recombination velocities of the minority carriers on the rear side of the base Sb1(D(ω, T);H) and Sb2(α, D(ω, T);H), are analyzed as a function of the dynamic diffusion coefficient (D(ω, T)), the absorption coefficient (α(λ)) and the thickness of the base (H). Thus their graphic representation makes it possible to go up, to the base optimum thickness (Hopt(ω, T)), for different temperature values and frequency ranges of modulation of monochromatic light, of strong penetration. The base optimum thickness (Hopt(ω, T)) decreases with temperature, regardless of the frequency range and allows the realization of the solar cell with few material (Si). 展开更多
关键词 Bifacial Silicon Solar Cell Absorption Coefficient Frequency TEMPERATURE Recombination Velocity Optimum thickness
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Fetal Thigh Circumference versus Fetal Abdominal Subcutaneous Tissue Thickness in Prediction of Fetal Weight in Term Pregnant Women
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作者 Mohamed El-Mandooh Aya Hassan Sarah Safwat 《Open Journal of Obstetrics and Gynecology》 2023年第9期1580-1594,共15页
Background: Fetal weight estimation by ultrasound is an important factor in obstetrics;it is directly related to the gestational age which helps to plan the mode of delivery and labor management. Objective: to compare... Background: Fetal weight estimation by ultrasound is an important factor in obstetrics;it is directly related to the gestational age which helps to plan the mode of delivery and labor management. Objective: to compare between fetal thigh circumference (TC) and abdominal subcutaneous tissue thickness (SCT) in estimating birthweight in term pregnant women. Patients and Methods: This prospective cohort study was conducted at outpatient clinic or emergency room, Obstetrics and Gynecology Department, Faculty of Medicine, Ain Shams University Maternity Hospitals from March 2022 until May 2023. During this study, 100 term pregnant females with gestational age 37 - 40 weeks attended El Demerdash Maternity Hospital and scheduled for delivery either at outpatient clinic or emergency room were enrolled, after consenting each of them. Basic fetal biometry was performed by an expert and professional medical personnel to ensure the accuracy of examination results. Fetal abdominal subcutaneous thickness and fetal thigh circumference were measured for assessment of gestational age and correlated with actual fetal body weight. In the current study, three formulas;Hadlock, Vintzileos’ and SCT formula were correlated with actual fetal body weight after birth. Results: The present study revealed that TC formula is closer to the actual birth weight, followed by Hadlock formula, while the SCT formula is the furthest from it. Conclusion: To increase the accuracy of birth estimations, regular ultrasound examinations should include fetal thigh circumference measurement. 展开更多
关键词 Fetal Thigh Circumference Fetal Abdominal Subcutaneous thickness Fetal Weight Term Pregnancy
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Macular and peripapillary retinal nerve fiber layer thickness in children with hyperopic anisometropic amblyopia 被引量:7
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作者 Shuang-Qing Wu Li-Wei Zhu +2 位作者 Qi-Bin Xu Jun-Li Xu Yu Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第1期85-89,共5页
AIM:To compare the retinal nerve fiber layer (RNFL) thickness and macular thickness in the amblyopic eye with that in the sound eye of children with hyperopic anisometropic amblyopia using optical coherence tomography... AIM:To compare the retinal nerve fiber layer (RNFL) thickness and macular thickness in the amblyopic eye with that in the sound eye of children with hyperopic anisometropic amblyopia using optical coherence tomography (OCT). METHODS:A prospective, nonrandom, intraindividual comparative cohort study includes 72 children with hyperopic anisometropic amblyopia in a single center. Macular thickness, macular foveola thickness, and peripapillary RNFL thickness were compared between the amblyopia eyes and the contralateral sound eyes. ·RESULTS:There were 38 male and 34 female patients, with a mean age as 9.7 ±1.9 years (range, 5-16 years). Hyperopic was +3.62±1.16D (range +2.00D to +6.50D) in the amblyopic eyes, which was significantly higher in the control eyes with +0.76±0.90D (range 0D to +2.00D) (P 【 0.01). The mean peripapillary RNFL thickness was 113.9± 7.2μm and 109.2 ±6.9μm in the amblyopic eye and the normal eye, respectively, reaching statistical significance (P = 0.02). The mean macular foveola thickness was significantly thicker in the amblyopic eyes than the contralateral sound eyes (181.4±14.2μm vs 175.2±13.3μm, P 【0.01), but the 1mm, 3mm or 6mm macular thickness central macular thickness was not significantly different. Degree of anisometropia in the contralateral eyes was not significantly correlated with differences of peripapillary RNFL, macular foveola thickness or central macular thickness. CONCLUSION:Eyes with hyperopic anisometropic amblyopia are found thicker macular foveola and peripapillary RNFL than the contralateral eyes in children. 展开更多
关键词 hyperopic anisometropic amblyopia retinal nerve fiber thickness macular thickness optical coherence tomography CHILDREN
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Preliminary Studies on Thickness of Nondestructive Rice (Oryza sativa L.) Leaf Blade 被引量:7
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作者 CHEN You-ding ZHANG Xu ZHOU Xin-qiao CHEN Guan-hua 《Agricultural Sciences in China》 CAS CSCD 2007年第7期802-807,共6页
Two varieties, Yuexinzhan and Guangchao 3, were used to study leaf thickness in rice in this experiment. The thickness of the leaf blade was measured by the nondestructive leaf thickness instrument, which was modified... Two varieties, Yuexinzhan and Guangchao 3, were used to study leaf thickness in rice in this experiment. The thickness of the leaf blade was measured by the nondestructive leaf thickness instrument, which was modified from the thickness instrument for steel objects (John Bull, England). The contacting area between the leaf and the probe of the instrument was 0.5 cm^2. There was no significant difference between the thickness of steel materials measured by the nondestructive rice leaf thickness instrument and the micrometer. The correlation between the thickness of the rice leaf blade measured by the nondestructive rice leaf thickness instrument and the specific leaf weight (SLW) was significant (P 〈 0.05 or P〈 0.01). The results also showed that the rice leaf thickness was uneven and asymmetric. The thickness and SLW of flag leaf tended to increase from the base to the tip of the leaf blade. The middle part of the second and third top leaf was the thickest, but no significant difference in thickness between the basal part and the fore part was found. Drawing a line on the main vein in the top three leaves, the left part was thinner than the right part. The thickness of the lower leaves (6/0-9/0) on the main culm tended to increase with increasing positions of the leaves in the early and middle stages, but the tendency was not the same for the higher leaves (10/0 upwards), although the higher leaves (10/0 upward) were thicker than the lower leaves (9/0 or downward). Furthermore, different CO2 concentrations (550±30, 460 ± 30 μmol mol^-1) in the growth boxes had no effect on the thickness of rice leaf blades. It can be concluded that the measurement of rice leaf thickness using the nondestructive rice leaf thickness instrument is simple, precise, and nondestructive. 展开更多
关键词 paddy rice leaf thickness nondestructive rice leaf thickness instrument
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Effect of Mg-Film Thickness on the Formation of Semiconductor Mg_2Si Films Prepared by Resistive Thermal Evaporation Method 被引量:3
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作者 余宏 谢泉 CHEN Qian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第3期612-616,共5页
Mg films of various thicknesses were deposited on Si(111) substrates at room temperature by resistive thermal evaporation method, and then the Mg/Si samples were annealed at 40 ℃ for 4 h. The effects of Mg film thi... Mg films of various thicknesses were deposited on Si(111) substrates at room temperature by resistive thermal evaporation method, and then the Mg/Si samples were annealed at 40 ℃ for 4 h. The effects of Mg film thickness on the formation and structure of Mg2Si films were investigated. The results showed that the crystallization quality of Mg2Si films was strongly influenced by the thickness of Mg film. The XRD peak intensity of Mg2Si (220) gradually increased initially and then decreased with increasing Mg film thickness. The XRD peak intensity of Mg2Si (220) reached its maximum when the Mg film of 380 um was used. The thickness of the Mg2Si film annealed at 400℃ for 4 h was approximately 3 times of the Mg film. 展开更多
关键词 Mg film thickness Mg2Si films Mg2Si films thickness thermal evaporation ANNEALING
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Analysis of thickness-shear and thickness-twist modes of AT-cut quartz acoustic wave resonator and filter 被引量:3
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作者 Zinan ZHAO Zhenghua QIAN +1 位作者 Bin WANG Jiashi YANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第12期1527-1538,共12页
The thickness-shear (TS) and thickness-twist (TT) vibrations of partially electroded AT-cut quartz plates for acoustic wave resonator and filter applications are theoretically studied. The plates have structural v... The thickness-shear (TS) and thickness-twist (TT) vibrations of partially electroded AT-cut quartz plates for acoustic wave resonator and filter applications are theoretically studied. The plates have structural variations in one of the two in-plane directions of the plates only. The scalar differential equations derived by Tiersten and Smythe for electroded and unelectroded AT-cut quartz plates are used, resulting in free vibration resonant frequencies and mode shapes for both fundamental and overtone fam- ilies of modes. The trapped modes with vibrations, mainly confined in the electroded areas, are found to exist in both the resonator and the filter structures. The numerical results for the trapped modes are presented for different aspect ratios of electrodes and material properties, providing a reference to the design and optimization of quartz acous- tic wave resonators and filters. 展开更多
关键词 quartz plate thickness-shear (TS) thickness-twist (TT) scalar equation trapped mode
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Measurement of Retinal Thickness in Normal Subjects with Retinal Thickness Analyzer 被引量:1
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作者 杨智宽 杜蜀华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1999年第4期314-318,共5页
The retinal thickness at posterior pole of normal subjects was mea-sured by using retinal thickness analyzer (RTA) to determine the values of retinal thickness and to establish map of retinal thickness in normal subje... The retinal thickness at posterior pole of normal subjects was mea-sured by using retinal thickness analyzer (RTA) to determine the values of retinal thickness and to establish map of retinal thickness in normal subjects. The retina of 6 mm× 6 mm in size (approximately 20°, centered on the macula) at the poste-rior pole was scanned by using RTA to obtain images of 116 normal eyes of 77cases of various age group. The irnages were processed by a computer to obtain the retinal thickness values and the thickness map of this location. The data were analyzed with SAS software package. The mean retinal thickness was 171. 77±26. 13 pm with no significant difference among the various age groups (P>0. 05).The thickness maps of the retina of 6 mm× 6 mm size at the posterior pole around the macula rendered a 'U'-shaped pattern, extending from the disc to the superior and inferior of the fovea. The retina was found to be thin at temporal side of the fovea, with the thinnest area being at the macula central fovea. The U-shaped pattern of the retinal thickness maps was well in agreement with the topography of the ganglion cells and the retinal nerve fibers in human retina. The measurement of the retinal thickness by RTA reflected the changes in the layers of ganglion cells and the retinal nerve fiber. Each scanning session of RTA examination can yield multiple optical cross-section images of the retina and obtain retinal thickness maps of posterior pole of living eyes. 展开更多
关键词 RETINA retinal thickness retinal thickness analyzer
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Cluster倾斜子范畴导出的Abel范畴的recollement和thick子范畴
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作者 林记 《中国科学技术大学学报》 CAS CSCD 北大核心 2014年第9期746-750,共5页
设T是三角范畴D的cluster倾斜子范畴.首先,如果D具有一个关于三角范畴D′和D″的recollement,且满足i*i*(T)T,j*j*(T)T,则给出了这个recollement诱导Abel范畴D/T关于Abel范畴D′/(i*T)和D″/(j*T)的recollement的充分必要条件;其次... 设T是三角范畴D的cluster倾斜子范畴.首先,如果D具有一个关于三角范畴D′和D″的recollement,且满足i*i*(T)T,j*j*(T)T,则给出了这个recollement诱导Abel范畴D/T关于Abel范畴D′/(i*T)和D″/(j*T)的recollement的充分必要条件;其次,如果H是D的thick子范畴,i*表示自然嵌入函子i*:H→D的左伴随函子,且i*TT,那么Abel范畴A′=H/(i*T)是Abel范畴A=D/T的thick子范畴. 展开更多
关键词 CLUSTER 倾斜子范畴 thick 子范畴
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