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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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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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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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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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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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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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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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Buoyance-driven hydrocarbon accumulation depth and its implication for unconventional resource prediction 被引量:25
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作者 Xiongqi Pang Chengzao Jia +6 位作者 Wenyang Wang Zhangxin Chen Maowen Li Fujie Jiang Tao Hu Ke Wang Yingxun Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第4期93-109,共17页
The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconve... The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconventional oil production in the USA accounted for 41%of the total oil production;and unconventional natural gas production in China accounted for 35%of total gas production,showing strong growth momentum of unconventional hydrocarbons explorations.Unconventional hydrocarbons generally coexist with conventional petroleum resources;they sometimes distribute in a separate system,not coexisting with a conventional system.Identification and prediction of unconventional resources and their potentials are prominent challenges for geologists.This study analyzed the results of 12,237 drilling wells in six representative petroliferous basins in China and studied the correlations and differences between conventional and unconventional hydrocarbons by comparing their geological features.Migration and accumulation of conventional hydrocarbon are caused dominantly by buoyance.Wepropose a concept of buoyance-driven hydrocarbon accumulation depth to describe the deepest hydrocarbon accumulation depth driven dominantly by buoyance;beyond this depth the buoyance becomes unimportant for hydrocarbon accumulation.We found that the buoyance-driven hydrocarbon accumulation depth in petroliferous basins controls the different oil/gas reservoirs distribution and resource potentials.Hydrocarbon migration and accumulations above this depth is dominated by buoyancy,forming conventional reservoirs in traps with high porosity and permeability,while hydrocarbon migration and accumulation below this depth is dominated by non-buoyancy forces(mainly refers to capillary force,hydrocarbon volumeexpansion force,etc.),forming unconventional reservoirs in tight layers.The buoyance-driven hydrocarbon accumulation depths in six basins in China range from 1200mto 4200 m,which become shallowerwith increasing geothermal gradient,decreasing particle size of sandstone reservoir layers,or an uplift in the whole petroliferous basin.The predicted unconventional resource potential belowthe buoyance-driven hydrocarbon accumulation depth in six basins in China is more than 15.71×10^(9) t oil equivalent,among them 4.71×10^(9) t reserves have been proved.Worldwide,94%of 52,926 oil and gas reservoirs in 1186 basins are conventional reservoirs and only 6%of them are unconventional reservoirs.These 94%conventional reservoirs show promising exploration prospects in the deep area below buoyance-driven hydrocarbon accumulation depth. 展开更多
关键词 Nature energy Fossil energy Oil and gas resources conventional hydrocarbon reservoirs Unconventional hydrocarbon reservoirs Buoyance-driven hydrocarbon accumulation DEPTH
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Theory, technology and prospects of conventional and unconventional natural gas 被引量:16
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作者 ZOU Caineng YANG Zhi +8 位作者 HE Dongbo WEI Yunsheng LI Jian JIA Ailin CHEN Jianjun ZHAO Qun LI Yilong LI Jun YANG Shen 《Petroleum Exploration and Development》 2018年第4期604-618,共15页
The development of natural gas in China has entered a golden and leap-forward stage, which is a necessary bridge to clean energy. This in-depth study on the status quo, theory, technology and prospect of natural gas d... The development of natural gas in China has entered a golden and leap-forward stage, which is a necessary bridge to clean energy. This in-depth study on the status quo, theory, technology and prospect of natural gas development shows:(1) The global remaining proven recoverable reserves of natural gas are 186×1012 m3, and the reserves-production ratio is 52.4, indicating a solid resource base for long-term and rapid development.(2) Ten formation and distribution laws of conventional and unconventional natural gas reservoirs have been proposed. In terms of exploration geology, the theory of conventional "monolithic" giant gas fields with different gas sources, and an unconventional gas accumulation theory with continuous distribution of "sweet areas" in different lithologic reservoirs have been established; in terms of development geology, a development theory of conventional structural gas reservoirs is oriented to "controlling water intrusion", while a development theory of unconventional gas is concentrated on man-made gas reservoirs.(3) With the geological resources(excluding hydrates) of 210×1012 m3 and the total proven rate of the resources less than 2% at present, the natural gas in China will see a constant increase in reserve and production; by 2030, the proven geological reserves of natural gas are expected to reach about(6 000-7 000)×108 m3, the production of conventional and unconventional natural gas each will reach about 1 000×108 m3, and the gas consumption will reach 5 500×108 m3. The dependence on imported natural gas may be 64% by 2030, and 70% by 2050.(4) Ten measures for future development of natural gas have been proposed, including strengthening exploration in large-scale resource areas, increasing the development benefits of unconventional gas, and enhancing the peak adjusting capacity of gas storage and scale construction of liquified natural gas. 展开更多
关键词 natural GAS GAS GEOLOGY conventional and UNconventional GAS GEOLOGY SHALE GAS tight GAS man-made GAS reservoir renewable energy controlling water INTRUSION LNG
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An efficient synthesis of benzofuran derivatives under conventional/non-conventional method 被引量:1
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作者 Suryakant B.Sapkal Kiran F.Shelke +1 位作者 Bapurao B.Shingate Murlidhar S.Shingare 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1439-1442,共4页
l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina(Al2O3) has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave ir... l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina(Al2O3) has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave irradiation to yield benzofuran derivatives. 展开更多
关键词 [meim]Br/Al2O3 BENZOFURAN CYCLOCONDENSATION conventional Non-conventional methods
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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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Effects of backward path parameters on formability in conventional spinning of aluminum hemispherical parts 被引量:4
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作者 甘甜 于忠奇 +2 位作者 赵亦希 S.A.EVSYUKOV 来新民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第2期328-339,共12页
During multi-pass conventional spinning, roller paths combined with the forward and the backward pass are usually used to improve the material formability. In order to understand the backward spinning process properly... During multi-pass conventional spinning, roller paths combined with the forward and the backward pass are usually used to improve the material formability. In order to understand the backward spinning process properly, the backward roller paths of hemispherical parts with aluminum alloy 2024-O are analyzed. Finite element model with parameterized conventional spinning roller paths, which are based on quadratic Bezier curves, is developed to explore the evolution of the stress, strain and thinning during the backward processes. Analysis of the simulation results reveals stress and strain features of backward pass spinning. According to the findings, the application of the backward pass can obviously improve the uniformity of wall thickness. Furthermore, references of the parameters in future backward path design are provided. 展开更多
关键词 conventional spinning multi-pass forming roller path design backward pass
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The Differences Between Conventional Poetry & Imagist Poetry
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作者 王抒飞 《海外英语》 2011年第9X期282-282,288,共2页
As a literary movement,Imagism,a strand of modernism,is a reaction to conventional poets.It was initiated in London at the dawn of the 20th century,but short-lived,and its effects reached British and American poetry.T... As a literary movement,Imagism,a strand of modernism,is a reaction to conventional poets.It was initiated in London at the dawn of the 20th century,but short-lived,and its effects reached British and American poetry.This thesis aims to find out the difference between imagist poetry and conventional poetry. 展开更多
关键词 imagist POETRY conventional POETRY
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Spinal cord biological safety of image-guided radiation therapy versus conventional radiation therapy 被引量:23
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作者 Wanlong Xu Xilinbaoleri +2 位作者 Hao Liu Ruozheng Wang Jingping Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第35期2755-2760,共6页
Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three m... Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three months after radiation, neuronal injury at the T9-10 levels was observed, including reversible injury induced by spinal image-guided radiation therapy and apoptosis induced by conventional radiation therapy. The number of apoptotic cells and expression of the proapoptotic protein Fas were significantly reduced, but expression of the anti-apoptotic protein heat shock protein 70 was significantly increased after image-guided radiation therapy compared with the conventional method of the same radiation dose. Moreover, the spinal cord cell apoptotic index positively correlated with the ratio of Fas/heat shock protein 70. These findings indicate that 3 months of radiation therapy can induce a late response in the spinal cord to radiation therapy; image-guided radiation therapy is safer and results in less neuronal injury compared with conventional radiation therapy. 展开更多
关键词 Image-guided radiation therapy conventional radiation therapy spinal cord NEURONS apoptosis FAS heat shock protein 70 biological safety vertebral body TUMOR
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Whole petroleum system and ordered distribution pattern of conventional and unconventional oil and gas reservoirs 被引量:21
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作者 Cheng-Zao Jia Xiong-Qi Pang Yan Song 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期1-19,共19页
The classical source-to-trap petroleum system concept only considers the migration and accumulation of conventional oil and gas in traps driven dominantly by buoyance in a basin,although revised and improved,even some... The classical source-to-trap petroleum system concept only considers the migration and accumulation of conventional oil and gas in traps driven dominantly by buoyance in a basin,although revised and improved,even some new concepts as composite petroleum system,total petroleum system,total composite petroleum system,were proposed,but they do not account for the vast unconventional oil and gas reservoirs within the system,which is not formed and distributed in traps dominantly by buoyancedriven.Therefore,the petroleum system concept is no longer adequate in dealing with all the oil and gas accumulations in a basin where significant amount of the unconventional oil and gas resources are present in addition to the conventional oil and gas accumulations.This paper looked into and analyzed the distribution characteristics of conventional and unconventional oil/gas reservoirs and their differences and correlations in petroliferous basins in China and North America,and then proposed whole petroleum system(WPS)concept,the WPS is defined as a natural system that encompasses all the conventional and unconventional oil and gas,reservoirs and resources originated from organic matter in source rocks,the geological elements and processes involving the formation,evolution,and distribution of these oil and gas,reservoirs and resources.It is found in the WPS that there are three kinds of hydrocarbons dynamic fields,three kinds of original hydrocarbons,three kinds of reservoir rocks,and the coupling of these three essential elements lead to the basic ordered distribution model of shale oil/gas reservoirs contacting or interbeded with tight oil/gas reservoirs and separated conventional oil/gas reservoirs from source rocks upward,which is expressed as“S\T-C”.Abnormal conditions lead to other three special ordered distribution models:The first is that with shale oil/gas reservoirs separated from tight oil/gas reservoirs.The second is that with two direction ordered distributions from source upward and downward.The third is with lateral distribution from source outside. 展开更多
关键词 conventional and unconventional oil and gas Petroleum system Whole petroleum system Hydrocarbon reservoirs ordered distribution model Fossil energy
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Optimal management for alcoholic liver disease: Conventional medications, natural therapy or combination? 被引量:14
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作者 Moon-Sun Kim Madeleine Ong Xianqin Qu 《World Journal of Gastroenterology》 SCIE CAS 2016年第1期8-23,共16页
Alcohol consumption is the principal factor in thepathogenesis of chronic liver diseases.Alcoholic liver disease(ALD)is defined by histological lesions on the liver that can range from simple hepatic steatosis to more... Alcohol consumption is the principal factor in thepathogenesis of chronic liver diseases.Alcoholic liver disease(ALD)is defined by histological lesions on the liver that can range from simple hepatic steatosis to more advanced stages such as alcoholic steatohepatitis,cirrhosis,hepatocellular carcinoma and liver failure.As one of the oldest forms of liver injury known to humans,ALD is still a leading cause of liver-related morbidity and mortality and the burden is exerting on medical systems with hospitalization and management costs rising constantly worldwide.Although the biological mechanisms,including increasing of acetaldehyde,oxidative stress with induction of cytochrome p4502E1,inflammatory cytokine release,abnormal lipid metabolism and induction of hepatocyte apoptosis,by which chronic alcohol consumption triggers serious complex progression of ALD is well established,there is no universally accepted therapy to prevent or reverse.In this article,we have briefly reviewed the pathogenesis of ALD and the molecular targets for development of novel therapies.This review is focused on current therapeutic strategies for ALD,including lifestyle modification with nutrition supplements,available pharmacological drugs and new agents that are under development,liver transplantation,application of complementary medicines,and their combination.The relevant molecular mechanisms of each conventional medication and natural agent have been reviewed according to current available knowledge in the literature.We also summarized efficacy vs safety on conventional and herbal medicines which are specifically used for the prevention and treatment of ALD.Through a system review,this article highlighted that the combination of pharmaceutical drugs with naturally occurring agents may offer an optimal management for ALD and its complications.It is worthwhile to conduct large-scale,multiple centre clinical trials to further prove the safety and benefits for the integrative therapy on ALD. 展开更多
关键词 ALCOHOLIC liver disease Alcohol HEPATITIS conventional MEDICINES NATURAL MEDICINES Hepaticlipid metabolism Hepatic inflammation Combinationtherapy
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Endoscopic diagnosis of cervical esophageal heterotopic gastric mucosa with conventional and narrow-band images 被引量:14
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作者 Chi-Liang Cheng Cheng-Hui Lin +3 位作者 Nai-Jen Liu Jui-Hsiang Tang Yen-Lin Kuo Yi-Ning Tsui 《World Journal of Gastroenterology》 SCIE CAS 2014年第1期242-249,共8页
AIM: To compare the diagnostic yield of heterotopic gastric mucosa (HGM) in the cervical esophagus with conventional imaging (CI) and narrow-band imaging (NBI).
关键词 Cervical esophagus Heterotopic gastric mucosa Endoscopic diagnosis Narrow-band imaging conventional imaging
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Three-dimensional MR and axial CT colonography versus conventional colonoscopy for detection of colon pathologies 被引量:12
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作者 Rahime Haykir Serdar Karakose +2 位作者 Aydin Karabacakoglu Mustafa Sahin Ertugrul Kayacetin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第15期2345-2350,共6页
AIM: To evaluate the sensitivity and specificity of MR colonography (MRC) and CT performance in detecting colon lesions, and to compare their sensitivity and specificity with that of conventional colonoscopy. METH... AIM: To evaluate the sensitivity and specificity of MR colonography (MRC) and CT performance in detecting colon lesions, and to compare their sensitivity and specificity with that of conventional colonoscopy. METHODS: Forty-two patients suspected of having colonic lesions, because of rectal bleeding, positive fecal occult blood test results or altered bowel habits, underwent the examinations. After insertion of a rectal tube, the colon was filled with 1000-1500 mL of a mixture of 9 g/L NaCI solution, 15-20 mL of 0.5 mmol/L gadopentetate dimeglumine and 100 mL of iodinized contrast material. Once colonic distension was achieved, three-dimensional gradient-echo (3D-GRE) sequences for MR colonography and complementary MR images were taken in all cases. Immediately after MR colonography, abdominal CT images were taken by spiral CT in the axial and supine position. Then all patients were examined by conventional colonoscopy (CC). RESULTS: The sensitivity and specificity of MRC for colon pathologies were 96.4% and 100%, respectively. The percentage of correct diagnosis by MRC was 97.6%. The sensitivity and specificity of CT for colon pathologies were 92.8%, 100%, respectively. The percentage of correct diagnosis by CT was 95.2%. CONCLUSION: In detecting colon lesions, MRC achieved a diagnostic accuracy similar to CC. However, MRC is minimally invasive, with no need for sedation or analgesics during investigation. There is a lower percentage of perforation risk, and all colon segments can be evaluated due to multi-sectional imaging availability; intramural, extra-intestinal components of colonic lesions, metastasis and any additional lesions can be evaluated easily. MRC and CT colonography are new radiological techniques that promise to be highly sensitive in the detection of colorectal mass and inflammatory bowel lesions. 展开更多
关键词 MR colonography CT colonography Colorectal mass Inflammatory bowel disease conventional colonoscopy
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