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Ab initio Structure Determination of [Co(NH_3)_5Br]Br_2 Using Conventional X-ray Powder Diffraction 被引量:1
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作者 Hong Xiang WU and Li Dun MA(Center for Analysis and Measuremnt, Fudan University, Shanghai, 200433)(Project supported by the National Natural Science Foundation of China(NSFC) NO. 29573098) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期647-648,共2页
The crystal structure of [Co(NH3)5Br]Br2 has been determined ab initio from the conventional X-ray powder diffraction data. The approximate structure with all 7 indeyendent non-H atoms was solved by direct methods. Th... The crystal structure of [Co(NH3)5Br]Br2 has been determined ab initio from the conventional X-ray powder diffraction data. The approximate structure with all 7 indeyendent non-H atoms was solved by direct methods. The final orthorhombic unit-cell parameters after Rietveld refinement are: a=13.6927, b=10.7071, c=6.9400A, V=1017.47A3, F30=93(0.0075,43), M20=49, Z=4. Space group is Pnma. The structure agreement factors are: Rp=0.066,Rwp=0.090, RF=0.041, RB=0.042. 展开更多
关键词 Br2 Using conventional x-ray Powder Diffraction Ab initio Structure Determination of NH3
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Improvements to conventional X-ray tube-based cone-beam computed tomography system 被引量:4
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作者 Cui Zhang Xiao-Dong Pan +2 位作者 Hong-Jie Shang Yan-Hong Luo Gong-Ping Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期156-164,共9页
Conventional X-ray tube-based cone-beam computed tomography(CX-CBCT) systems have great potential in industrial applications. Such systems can rapidly obtain a three-dimensional(3D) image of an object.Conventional X-r... Conventional X-ray tube-based cone-beam computed tomography(CX-CBCT) systems have great potential in industrial applications. Such systems can rapidly obtain a three-dimensional(3D) image of an object.Conventional X-ray tubes fulfill the requirements for industrial applications, because of their high tube voltage and power. Continuous improvements have been made to CX-CBCT systems, such as imaging time shortening,acquisition strategy optimization, and imaging software development, etc. In this study, a CX-CBCT system is developed. Additionally, some improvements to the CX-CBCT system are proposed based on the hardware conditions of the X-ray tube and detector. A near-detector(ND)geometry condition is employed to obtain a sharper image and larger detection area. An improved acquisition strategy is proposed to simplify operations and reduce total imaging time. In the ND geometry condition, a simplified method called FBP slice stacking(SS-FBP) is proposed, which can be applied to 3D image reconstruction. SS-FBP is timesaving relative to traditional methods. Furthermore, imaging software for the CX-CBCT system is developed in the MATLAB environment. Several imaging experiments were performed. The results suggest that the CX-CBCT system works properly, and that the above improvements are feasible and practical. 展开更多
关键词 CONE-BEAM CT conventional x-ray TUBE NONDESTRUCTIVE testing x-ray imaging
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Conventional Geothermal Systems and Unconventional Geothermal Developments: An Overview 被引量:1
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作者 Maryam Khodayar Sveinbjörn Björnsson 《Open Journal of Geology》 CAS 2024年第2期196-246,共51页
This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal syste... This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. Medium-temperature (MT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at <7 Km depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. Meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development. 展开更多
关键词 conventional Geothermal Systems Unconventional Geothermal Developments Shallow and Deep Closed-Loops Enhanced Geothermal Systems Supercritical and Millimeter-Wave Drilling
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Large Conventional Osteosarcoma of the Proximal Humerus in a 13-Year-Old Child: Case Report
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作者 Lucienne Irène Patricia Ondima Rhodia Hélène Bosseba Missengue +7 位作者 Cardinale Princilia Okiemy Niendet Nuptia Erica Akobande Jean Claude Mieret Caryne Mboutol-Mandavo Redy Atipo Galloye Judith Nsondé Malanda Jennifer Mave Sirimé Ngandzo Fabien Mouamba 《Open Journal of Pediatrics》 2024年第2期297-304,共8页
Introduction: Osteosarcoma is the most common primary malignant bone tumor in children. It is highly aggressive and has a poor prognosis. A late presentation modifies and makes difficult the management affecting the s... Introduction: Osteosarcoma is the most common primary malignant bone tumor in children. It is highly aggressive and has a poor prognosis. A late presentation modifies and makes difficult the management affecting the survival of children. We report the case of a large conventional osteosarcoma in a 13-year-old girl. Case Presentation: Adolescent girl admitted for painful swelling of the left shoulder with absolute functional impotence of the thoracic limb and severe anemia. The painful swelling was thought to have been caused by a minor trauma that had occurred six months previously. The patient’s general condition was poor, and she presented with a large, shiny, painful mass over the shoulder and upper 2/3 of the left arm, measuring 28 cm long by 28 cm wide and 57 cm in circumference, and a large fistulous axillary adenopathy. CT scan showed a tumour lesion of the left humerus with liver and lung metastases, raising suspicion of osteogenic osteosarcoma. The tumor was classified according to TNM staging: T2N1M1(a + b). Management was modified when uncontrolled bleeding developed. It consisted of an extended amputation of the left thoracic limb. Pathological analysis showed a high-grade conventional osteosarcoma. Quality improvement was obtained for thirty days, followed by the onset of dyspnea. The evolution was towards death at forty days post-operatively. Conclusion: Osteosarcoma is a highly aggressive cancer. Delayed treatment leads to a fatal outcome. Early diagnosis is one of the challenges to be met in order to improve survival. 展开更多
关键词 OSTEOSARCOMA CHILD conventional Case Report
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Spinal Analgesia with Intrathecal Morphine versus Conventional Analgesia after Laparoscopic Colectomy: A Retrospective Cohort Study
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作者 Lionel Diyamona Manon Colin +12 位作者 Marc Léone Laurent Zieleskiewicz Joseph Nsiala Wilfrid Mbombo Rachel Mbala Bruno Pastene Chris Nsituavibidila Dan Kankonde Gracia Likinda Jean Claude Mubenga Khazy Anga Noelly Mukuna Christel Isengingo 《Open Journal of Anesthesiology》 2024年第7期159-174,共16页
Objective: Postoperative pain (POP) following abdominal surgery can vary from a few hours to several days. This acute, unrelieved pain can become chronic, requiring patients to take analgesics on an almost daily basis... Objective: Postoperative pain (POP) following abdominal surgery can vary from a few hours to several days. This acute, unrelieved pain can become chronic, requiring patients to take analgesics on an almost daily basis for comfort. Analgesia using general opioids has many side effects and intrathecal morphine is a good alternative. This study was conducted to evaluate the efficacy of intrathecal morphine (ITM) versus conventional analgesia in the management of postoperative pain in colectomy performed by laparoscopic surgery. Methods: Cohort study conducted at the Hôpital Nord in Marseille, from 01 January to 31 July 2021 in patients aged at least 18 years undergoing anaesthesia for scheduled colectomy by laparoscopic surgery. The primary endpoint was postoperative pain intensity and the secondary endpoints were morphine consumption, treatment side effects and length of hospital stay. Statistical analysis was performed using XLSTAT software. Results: We included 193 patients: 131 in the control group (conventional analgesia) and 62 in the ITM group. We observed: a significant decrease in pain (assessed by numerical scale) in favour of the ITM group in the post-anaesthetic care room, i.e. 3 (±4) vs 1 (±2), p 0 and H2: 2 (±2) vs. 1 (±2);p Conclusion: These results suggest that intrathecal morphine (ITM) in laparoscopic colectomy provides effective postoperative analgesia with low morphine consumption, and a reduction in morphine side-effects compared with conventional analgesia. 展开更多
关键词 Intrathecal Morphine COLECTOMY LAPAROSCOPY conventional Analgesia
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Comparative Analysis of Lactuca sativa Growth Using Compost Versus Conventional Soil
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作者 Sofia Huber Galen Papkov +4 位作者 Xiusheng Yang John Griffis Kathryn Jackson Sarah Bauer Ankit Kumar Singh 《Agricultural Sciences》 2024年第11期1223-1235,共13页
Conventional agricultural techniques have been degrading American soils nationwide since the beginnings of modern-day agriculture through practices such as soil tilling, using nitrogen synthetic fertilizers, and monoc... Conventional agricultural techniques have been degrading American soils nationwide since the beginnings of modern-day agriculture through practices such as soil tilling, using nitrogen synthetic fertilizers, and monocultural systems. These techniques contribute to degrading soil health, mass emissions of carbon dioxide into the atmosphere, and decreased biodiversity. Regenerative agriculture techniques include the utilization of cover crops, compost, no-tillage, the integration of livestock, and crop rotation. The APS Laboratory for Sustainable Agriculture focused on the effectiveness of compost by comparing the growth of lettuce in four different treatments: 100% Compost (100%C), 75% Compost 25% Miracle-Gro (75%C - 25%MG), 50% Compost 50% Miracle-Gro (50%C - 50%MG), and finally, 100% Miracle-Gro (100%MG). The lettuce seeds were kept in a growth tent for fifteen days during their period of germination before being transferred to four 1 × 1 × 0.15 m plots in the Food Forest at Florida Gulf Coast University (FGCU) for the 60-day growth period. The lettuce crops grew to full bloom and were ready for harvest. Sampling events took place every six days in which crop growth data including wet weight (g), dry weight (g), nitrogen (mg/g), chlorophyll concentration (mg/cm2), and leaf area (LA) (cm2) were collected. Statistical analysis was then conducted from the data. Based on the statistical tests conducted at the 5% significance level using R statistical software, soil treatment type was found to be significant (p = 0.0002). Soil treatment type was shown to have significantly impacted wet weight (p χ2 [3] = 3.91, p = 0.2717). 100%C and 100%MG of soil treatments produced the most successful lettuce crops. The 100%C soil treatment yielded lettuce crops with the heaviest wet weights and the largest LAs, and the 100% MG soil treatment yielded the heaviest dry weights and the highest nitrogen readings. Results demonstrate the effectiveness and feasibility of using compost as a technique for regenerative agriculture. 展开更多
关键词 COMPOST conventional Agriculture LETTUCE Regenerative Agriculture Soil Health
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Numerical Investigation of Combined Production of Natural Gas Hydrate and Conventional Gas
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作者 Hongzhi Xu Jian Wang +3 位作者 Shuxia Li Fengrui Zhao Chengwen Wang Yang Guo 《Fluid Dynamics & Materials Processing》 EI 2024年第3期505-523,共19页
Natural gas hydrate(NGH)is generally produced and accumulated together with the underlying conventional gas.Therefore,optimizing the production technology of these two gases should be seen as a relevant way to effecti... Natural gas hydrate(NGH)is generally produced and accumulated together with the underlying conventional gas.Therefore,optimizing the production technology of these two gases should be seen as a relevant way to effectively reduce the exploitation cost of the gas hydrate.In this study,three types of models accounting for the coexistence of these gases are considered.Type A considers the upper hydrate-bearing layer(HBL)adjacent to the lower conventional gas layer(CGL);with the Type B a permeable interlayer exists between the upper HBL and the lower CGL;with the type C there is an impermeable interlayer between the upper HBL and the lower CGL.The production performances associated with the above three models are calculated under different conditions,including only a depressurized HBL(only HBL DP);only a depressurized CGL(only CGL DP);and both the HBL and the CGL being depressurized(HBL+CGL DP).The results show that for Type A and Type B coexistence accumulation models,when only HBL or CGL is depressurized,the gas from the other layer will flow into the production layer due to the pressure difference between the two layers.In the coexistence accumulation model of type C,the cumulative gas production is much lower than that of Type A and Type B,regardless of whether only HBL DP,only CGL DP,or HBL+CGL DP are considered.This indicates that the impermeable interlayer restricts the cross-flow of gas between HBL and CGL.For three different coexistence accumulation models,CGL DP has the largest gas-to-water ratio. 展开更多
关键词 Natural gas hydrate conventional gas coexistence accumulation DEPRESSURIZATION combined production
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Analysis of Maximum Liquid Carrying Capacity Based on Conventional Tubing Plunger Gas Lift
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作者 Yanqun Yu Wenhao Xu +3 位作者 Yahui Huangfu Jinhai Liu Bensheng Wang Kai Liu 《Energy Engineering》 EI 2024年第6期1521-1533,共13页
China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable prod... China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable productionof these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately graspthe drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift inthe plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellboreconfigurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculationmethod for the maximum daily fluid production rate based on the work regime with the highest fluid recovery ratewere determined. For the first time, the critical flow rate method was proposed as a constraint for the maximumliquid-carrying capacity of the plunger-lift, and liquid-carrying capacity charts for conventional plunger-lift withdifferent casing sizes were developed. The results showed that for 23/8 casing plunger-lift, with a well depth ofshallower than 808 m, the maximum drainage rate was 33 m3/d;for 27/8 casing plunger-lift, with a well depth ofshallower than 742 m, the maximum drainage rate was 50.15 m3/d;for 31/2 casing plunger-lift, with a well depthof shallower than 560 m, the maximum drainage rate was 75.14 m3/d. This research provides a foundation for thescientific selection of plunger-lift technology and serves as a decision-making reference for developing reasonableplunger-lift work regimes. 展开更多
关键词 Unconventional well conventional tubing string plunger gas lift critical flow rate liquid carry-over chart version
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Comparative analysis of conventional laparoscopic surgery and single-incision laparoscopic surgery in gastric cancer treatment:Outcomes and prognosis
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作者 Ce Cao Xue Tian +1 位作者 Xue-Zhao Wang Qing Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3786-3793,共8页
BACKGROUND Gastric cancer surgery has advanced with minimally invasive techniques.This study compares outcomes between single-incision laparoscopic surgery plus one port(SILS+1)and conventional laparoscopic surgery(CL... BACKGROUND Gastric cancer surgery has advanced with minimally invasive techniques.This study compares outcomes between single-incision laparoscopic surgery plus one port(SILS+1)and conventional laparoscopic surgery(CLS)in treating gastric cancer.AIM To explore the curative effect of SILS+1 and CLS on gastric cancer and their influences on prognosis.METHODS A total of 93 patients with gastric cancer undergoing radical gastrectomy in the hospital were retrospectively analyzed between September 2019 and September 2022.According to different surgical methods,they were divided into SILS+1 group(n=56)and CLS group(n=37).The perioperative indexes,pain degree[visual analogue scale(VAS)]and stress response[C-reactive protein(CRP),white blood cell count(WBC)]in the two groups were compared.The postoperative complications,recurrence rate and mortality at 1 year after surgery were recorded.RESULTS Intraoperative blood loss was significantly lower in the SILS+1 group(76.53±8.12 mL)compared to the CLS group(108.67±12.34 mL,P<0.001),and the total incision length was also significantly shorter in the SILS+1 group(5.29±1.01 cm vs 9.45±2.34 cm,P<0.001).SILS+1 patients experienced faster recovery,with shorter times to first flatus(1.94±0.43 days vs 3.23±0.88 days,P<0.001)and ambulation(2.76±0.58 days vs 4.10±0.97 days,P<0.001).Postoperative pain,as measured by VAS scores,was significantly lower in the SILS+1 group on postoperative days 1,2,and 3(P<0.001).Additionally,stress markers(CRP and WBC)were significantly lower in the SILS+1 group on the first postoperative day(CRP:6.41±1.63 mg/L vs 7.82±1.88 mg/L,P<0.001;WBC:6.34±1.50×109/L vs 7.09±1.61×109/L,P=0.024).The complication rate in the SILS+1 group was also significantly lower than in the CLS group(8.93%vs 27.03%,P=0.020).However,there was no significant difference in recurrence rates between the two groups after one year(3.57%vs 8.11%,P>0.05).CONCLUSION SILS+1 and CLS have the comparable lymph node clearance effect in patients with gastric cancer.However,SILS+1 is more beneficial to reduce intraoperative blood loss,relieve pain,alleviate stress response,reduce the incidence of complications and promote rapid postoperative recovery. 展开更多
关键词 Single-incision laparoscopic surgery+1 port conventional laparoscopic surgery Radical gastrectomy Gastric cancer RECURRENCE
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Diagnostic Value of the Thoracic Ultrasonography Compared to Conventional Chest X-Rays in Pneumonia for Children between 0 to 15 Years: Case Study in Two Hospitals in Yaoundé 被引量:2
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作者 Seme Engoumou Ambroise Merci Mbede Maggy +3 位作者 Awana Armel Philippe Bilounga Ndengue Priscille Edith Onguene Julienne Zeh Odile Fernande 《Open Journal of Radiology》 2019年第1期10-19,共10页
Introduction: The diagnosis of pneumonia is usually made based on clinical manifestations and chest X-ray. The use of ultrasound in detecting pulmonary diseases in general, and especially consolidation syndrome has be... Introduction: The diagnosis of pneumonia is usually made based on clinical manifestations and chest X-ray. The use of ultrasound in detecting pulmonary diseases in general, and especially consolidation syndrome has been demonstrated. The objective of this study was to determine the accuracy of thoracic ultrasound compared to chest X-ray in the diagnosis of infectious pneumonia in children. Methods: Children between 0 to 15 years were included in our study. The lung ultrasound results obtained were compared with those of the chest X-ray used as the reference. Our data were introduced into the EpiInfo 3.5.4 software and analyzed with the EpiInfo 3.5.4 and IBMSPSS Statistics version 20.0 softwares. Microsoft Office Excel 2016 was used to produce Charts. Continuous quantitative variables were presented. Cohen’s Kappa concordance test was applied with confidence interval of 95%. Results: 52 children were enrolled in the study. In imaging, the dominant sign was consolidation syndrome (75.0%) of cases by chest radiography, and in 78.8% of cases by lung ultrasound (p Conclusion: Our study demonstrated that lung echography is a non-ionizing and reliable tool in the diagnosis of childhood’s pneumonia. 展开更多
关键词 LUNG Ultrasound CHEST x-ray PNEUMONIA CHILDREN Yaoundé Cameroon
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Comparative study of conventional urosonography without contrast enhancement and x-ray voiding cystourethrography for diagnosis of vesicoureteral reflux in children 被引量:1
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作者 Nadide Basak Gulleroglu Kaan Gulleroglu Esra Baskin 《Discussion of Clinical Cases》 2020年第4期9-14,共6页
Background:Vesicoureteral reflux is the most common urinary congenital anomaly in children.Given the risk associated with radiation exposure there has been an increasing need for radiation-free method in the diagnosis... Background:Vesicoureteral reflux is the most common urinary congenital anomaly in children.Given the risk associated with radiation exposure there has been an increasing need for radiation-free method in the diagnosis and follow-up of the vesicoureteral reflux.The aim of our study is to compare conventional urosonography without contrast enhancement and x-ray voiding cystourethrography.Patients and Methods:Children with recurrent urinary tract infection with suspected vesicoureteral reflux were included to the study.Vesicoureteral reflux is demonstrated and graded by x-ray voiding cystourethrography.DMSA is used for the evaluation of renal scar.Conventional sonographic procedure was performed in all patients.Ureterovesical junction insertion angle was evaluated.The diameter and length of the ureterovesical junction were also measured.Results:268 children enrolled to the study.Vesicoureteral reflux was demonstrated in 62 children by x-ray voiding cystourethrography.Ureterovesical junction insertion angle measurement had a statistically significant relation for right and left vesicoureteral reflux presence(right:r:.646,p:.01 and left:r:.446,p:.01).Diagnosis sensitivity of vesicoureteral reflux with conventional ultrasonography is 95.10%and specificity is 81%(Youden’s index 76.1%)for the cutoff value of the ureterovesical junction insertion angle is 28.6 degrees.Positive predictive value is 87.2%,negative predictive value is 94.73%and diagnostic accuracy is 86.29%with conventional ultrasonography.Conclusions:Measurement of ureterovesical junction insertion angle,length and diameter by conventional urosonography is an easy accessible and cheap technique with high sensitivity and specificity for the diagnosis and followup of the vesicoureteral reflux without exposure to ionizing radiation. 展开更多
关键词 Vesicoureteral reflux conventional urosonography x-ray voiding cystourethrography Ureterovesical junction insertion angle
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Observation on the Effect of Non-Invasive Ventilator Combined with Conventional Therapy in the Treatment of Chronic Obstructive Pulmonary Disease Complicated with Respiratory Failure
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作者 Cheng Shi 《Journal of Clinical and Nursing Research》 2024年第2期104-110,共7页
Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.M... Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:68 patients with COPD combined with respiratory failure treated in our hospital from September 2021 to October 2023 were selected as the research subjects.Using the random number table method,they were divided into a control group and an experimental group of 34 cases each.The control group received conventional symptomatic treatment,and the experimental group received non-invasive ventilator treatment based on the control group.The clinical effects,blood gas indicators(partial pressure of carbon dioxide(PaCO_(2)),partial pressure of oxygen(PaO_(2)),arterial oxygen saturation(SaO_(2))),lung function(forced expiratory volume in 1 second(FEV1),forced vital capacity(FVC),6 min walking distance),complications,and inflammatory factor levels(c-reactive protein(CRP),interleukin-6(IL-6),neutrophil-to-lymphocyte ratio(NLR))of the two groups of patients were observed.Results:(1)The clinical efficacy of the patients in the experimental group(33/97.06%)was more significant as compared with the control group(25/73.53%)(P<0.05);(2)After treatment,the clinical efficacy of the two groups of patients in terms of FEV1,FEV1/FVC,6-minute walking distance,PaO_(2)and SaO_(2)all increased in the experimental group as compared to that of the control group(P<0.05);(3)After treatment,the PaCO_(2),CRP,IL-6,and NLR of the two groups of patients decreased,and the decrease in the experimental group was higher than that of the control group(P<0.05);(4)The patients’complication rate in the experimental group(2/5.88%)was lower as compared to that of the control group(9/26.46%)(P<0.05).Conclusion:Non-invasive ventilators combined with conventional therapy achieved good clinical results in treating patients with COPD and respiratory failure. 展开更多
关键词 Non-invasive ventilator conventional therapy Chronic obstructive pulmonary disease Respiratory failure Clinical effect
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Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope
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作者 Qiang Liu Xiang Li +3 位作者 Shen Du Ming Gao Yanbin Yin Jiongming Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期102-110,共9页
During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a rest... During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the mold.In which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid slag.In contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive information.Therefore,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding times.The results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles increases.In addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually decreases.In one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the large.These findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels. 展开更多
关键词 mold flux low basicity BUBBLES three-dimensional x-ray microscope VISCOSITY
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Study on the Effect of Repetitive Peripheral Magnetic Stimulation Combined with Conventional Rehabilitation Measures on Shoulder Dysfunction in Early Stroke
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作者 Hui Yan Mingmei Ding +2 位作者 Ye Xu Zhen Ma Xiaoqing Ma 《Journal of Clinical and Nursing Research》 2024年第2期44-49,共6页
Objective:To study the effect of repetitive peripheral magnetic stimulation(rPMS)combined with conventional rehabilitation measures on shoulder dysfunction in early stroke.Methods:60 patients with shoulder dysfunction... Objective:To study the effect of repetitive peripheral magnetic stimulation(rPMS)combined with conventional rehabilitation measures on shoulder dysfunction in early stroke.Methods:60 patients with shoulder dysfunction in early stroke were selected,and all of them were admitted to our hospital from August 2021 to August 2023.The patients were randomly grouped into a control group(conventional rehabilitation measures intervention,30 cases)and an intervention group(rPMS and conventional rehabilitation measures intervention,30 cases)according to the lottery method.The pain scores,shoulder mobility,and motor function scores of the two groups were compared.Results:The pain score was lower in the intervention group,and the shoulder mobility and motor function scores were higher in the intervention group(P<0.05)as compared to that of the control group.Conclusion:The effect of combining rPMS and conventional rehabilitation measures in treating shoulder dysfunction in early stroke was remarkable and should be popularized. 展开更多
关键词 Repetitive peripheral magnetic stimulation conventional rehabilitation measures Early stroke Shoulder joint function
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Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography
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作者 WU Min CAO Kailei +4 位作者 XIAO Weirong YU Zetai CAO Jierong DING Qingjun LI Jinhui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期164-170,共7页
The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an ... The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 versa.The results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack time.In addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate erosion.The damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC pastes.Furthermore,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution. 展开更多
关键词 CONCRETE external sulfate attack damage evolution situ x-ray computed tomography
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Comparison between Predicted and Measured X-Ray Output in Some Conventional Radiography Units
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作者 Calvin Didier Njiki Yolande Huguette Ebele Yigbedeck +1 位作者 Joseph Eric Martial Ndjaka Manyol Thierry Ndzana Ndah 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2019年第4期204-210,共7页
This study aims to investigate how accurate are TASMICS and TASMIP models in predicting the X-ray output of some Conventional Radiology X-ray units with high frequency generators. The X-ray output in microgray per mil... This study aims to investigate how accurate are TASMICS and TASMIP models in predicting the X-ray output of some Conventional Radiology X-ray units with high frequency generators. The X-ray output in microgray per milliampere seconds (μGy/mAs) at 100 cm from the X-ray tube was determined for selected high voltages and taking into account the total filtration. The X-ray output was then measured directly with the multi-purpose detectors (MPD), Raysafe X2. The maximum relative error between measured and predicted values was found to be equal to 20%. The maximum relative error between measured and predicted values obtained demonstrates the difficulty of accurately predicting the X-ray tube output using TASMICS and TASMIP models since they are based on fixed anode angles and different composition of the tungsten anode. 展开更多
关键词 x-ray SPECTRA TASMICS TASMIP
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Difference of Nitrogen Uptake and Use Efficiency in Conventional Indica Rice Cultivars with Different Nitrogen Use Efficiency for Grain Output 被引量:3
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作者 周娟 李进前 +4 位作者 张彪 张传胜 张岳芳 王余龙 董桂春 《Agricultural Science & Technology》 CAS 2008年第6期68-73,141,共7页
[Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice... [Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice cultivars were solution-cultured in 2001 and 2002, respectively. Dry matter weight (including root system, culm and sheath, leaves, panicle), nitrogen content of different organs, yield and its components were measured. The tested rice cultivars were classified into 6 types (i.e. A, B, C, D, E and F, A was the lowest, and F was the highest) based on their NUEg level by the MinSSw method.[Result](1)Difference of NUEg of the cultivars used in this study were very large; (2) No significant difference of N content at heading stage was observed among different NUEg types of indica rice. In the cultivars with higher NUEg, however, N content in leaf, stem-sheath and entire rice plant were lower at mature stage. (3)Cultivars with higher NUEg were characterized with lower N uptake before heading and at mature stage; (4) Cultivars with higher NUEg were characterized with higher N use efficiency in biomass production and harvest index. [Conclusion] The cultivars with higher NUEg showed lower N uptake and N content, while nitrogen use efficiency was higher. 展开更多
关键词 conventional INDICA rice CULTIVARS NITROGEN content for grain output NITROGEN UPTAKE NITROGEN use efficiency
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地震工程中的Conventional Pushover和Adaptive Pushover分析法 被引量:2
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作者 邓芃 王来 刘艳 《山东科技大学学报(自然科学版)》 CAS 2005年第2期114-117,共4页
阐述了ConventionalPushover分析法的基本原理和方法,指出固定侧向力加载模式的缺陷;由于AdaptivePushover分析法考虑了结构刚度退化、高阶振型的影响、地震反应谱理论以及SRSS或CQC振型组合的综合作用,同固定侧向力加载模式相比,对结... 阐述了ConventionalPushover分析法的基本原理和方法,指出固定侧向力加载模式的缺陷;由于AdaptivePushover分析法考虑了结构刚度退化、高阶振型的影响、地震反应谱理论以及SRSS或CQC振型组合的综合作用,同固定侧向力加载模式相比,对结构受力状态的模拟更加准确。指出Pushover分析法尚存在的问题。 展开更多
关键词 Adaptive 分析法 地震工程 反应谱理论 基本原理 刚度退化 高阶振型 综合作用 受力状态 侧向力 模式 结构
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Analysis of Yield Traits in Conventional Rice Varieties
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作者 张现伟 李经勇 +3 位作者 郑家奎 姚雄 甘兴友 唐永群 《Agricultural Science & Technology》 CAS 2016年第4期852-856,共5页
From the breeding of conventional dwarf rice varieties in the 1960 s to rice heterosis utilization in the 1970 s, the improvement of yield traits has been a primary goal of rice breeding. However, the yield potential ... From the breeding of conventional dwarf rice varieties in the 1960 s to rice heterosis utilization in the 1970 s, the improvement of yield traits has been a primary goal of rice breeding. However, the yield potential of multiple hybrid rice varieties bred successfully in recent twenty years is not significantly higher than that of early bred rice varieties. Due to continuous development and application of new germplasm resources, the yield of conventional rice varieties has been improved constantly. Currently, the yield of some conventional rice varieties is higher than that of hybrid rice. In order to clarify differences between the yield of conventional rice and hybrid rice, and reevaluate conventional rice varieties, in this study, conventional rice and hybrid rice combinations with the same genetic background were compared to analyze the yield and related traits of these 12 combinations. In the comparative experiments of 12 combinations of conventional rice and hybrid rice, the combinations in which yield of hybrid rice was significantly higher than that of conventional rice accounted for 41.7%; the combinations in which yield of conventional rice was higher than that of hybrid rice accounted for 16.6%; the combinations in which no significant differences were found between the yield of conventional rice and hybrid rice accounted for 41.7%. The yield of several conventional rice varieties was equal to or even higher than that of hybrid rice with the same genetic background. This study could provide theoretical reference for the genetic breeding, popularization and application of conventional rice. 展开更多
关键词 conventional rice Hybrid rice YIELD
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Epigenetic Effects of Special Plant Nutritional Elements(SPNE) on Four Generations of Conventional Rice
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作者 余素芹 田长恩 +2 位作者 谢国文 常绍明 胡位荣 《Agricultural Science & Technology》 CAS 2014年第11期1888-1893,1898,共7页
[Objective] The epigenetic effects of special plant nutritional elements (SP-NE) on 4 generations of conventional rice were investigated. [Method] The 4 gener-ations of a conventional rice cultivar were al treated w... [Objective] The epigenetic effects of special plant nutritional elements (SP-NE) on 4 generations of conventional rice were investigated. [Method] The 4 gener-ations of a conventional rice cultivar were al treated with the SPNE. The effects of SPNE on the yield of the 4 generations were investigated. From the 1st generation to the 4th generations, some seeds were treated with the SPNE and water alterna-tively, and some seeds were treated with the SPNE persistently. Under these condi-tions, the effects of SPNE on the yield of rice were studied. In addition, the epige-netic effects of spraying times of SPNE on the yield of rice within the same gener-ation were studied. According to the national standard for pol utant content in food (GB 2762-2012), the heavy metal content, particularly the Cd content, and the pro-tein content in rice grains were determined. [Result] The increase and the epigenetic increase of yield of rice treated with SPNE were al enlarged generation by genera-tion. The yield differed among different plots even under the same SPNE treatment. But the yield increase was similar within the same plot. The epigenetic effects of spraying times of SPNE on the yield were also similar. The pol utant content in rice grains was al less than the limited content required by the national standard. The Cd content was lower and the protein content was higher in the rice treated with SPNE compared to that in the rice treated with water, indicating the rice treated with SPNE was more safe and nutritional. [Conclusion] We hope to provide a theo-retical basis for the production of conventional rice. 展开更多
关键词 SPNE conventional rice Epigenetic effects Four generations
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