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Bayesian partial pooling to reduce uncertainty in overcoring rock stress estimation
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作者 Yu Feng Ke Gao Suzanne Lacasse 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1192-1201,共10页
The state of in situ stress is a crucial parameter in subsurface engineering,especially for critical projects like nuclear waste repository.As one of the two ISRM suggested methods,the overcoring(OC)method is widely u... The state of in situ stress is a crucial parameter in subsurface engineering,especially for critical projects like nuclear waste repository.As one of the two ISRM suggested methods,the overcoring(OC)method is widely used to estimate the full stress tensors in rocks by independent regression analysis of the data from each OC test.However,such customary independent analysis of individual OC tests,known as no pooling,is liable to yield unreliable test-specific stress estimates due to various uncertainty sources involved in the OC method.To address this problem,a practical and no-cost solution is considered by incorporating into OC data analysis additional information implied within adjacent OC tests,which are usually available in OC measurement campaigns.Hence,this paper presents a Bayesian partial pooling(hierarchical)model for combined analysis of adjacent OC tests.We performed five case studies using OC test data made at a nuclear waste repository research site of Sweden.The results demonstrate that partial pooling of adjacent OC tests indeed allows borrowing of information across adjacent tests,and yields improved stress tensor estimates with reduced uncertainties simultaneously for all individual tests than they are independently analysed as no pooling,particularly for those unreliable no pooling stress estimates.A further model comparison shows that the partial pooling model also gives better predictive performance,and thus confirms that the information borrowed across adjacent OC tests is relevant and effective. 展开更多
关键词 Overcoring stress measurement Uncertainty reduction Partial pooling Bayesian hierarchical model Nuclear waste repository
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U-Net Based Dual-Pooling Segmentation of Bone Metastases in Thoracic SPECT Bone Scintigrams
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作者 Yang He Qiang Lin +1 位作者 Yongchun Cao Zhengxing Man 《Journal of Computer and Communications》 2024年第4期60-71,共12页
In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of disti... In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of distinct feature encoding and decoding stages, with dual-pooling modules employed in encoding stages to maintain the background information needed for bone scintigrams diagnosis. Both the DAC and RMP modules are utilized in the bottleneck layer to address the multi-scale problem of metastatic lesions. Experimental evaluations on 306 clinical SPECT data have demonstrated that the proposed method showcases a substantial improvement in both DSC and Recall scores by 3.28% and 6.55% compared the baseline. Exhaustive case studies illustrate the superiority of the methodology. 展开更多
关键词 Tumor Bone Metastasis Bone Scintigram Lesion Segmentation CNN Dual pooling
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Expanding the liver donor pool worldwide with hepatitis C infected livers, is it the time?
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作者 Mai Hashem Mohammed A Medhat +1 位作者 Doaa Abdeltawab Nahed A Makhlouf 《World Journal of Transplantation》 2024年第2期13-27,共15页
Liver transplantation(LT)provides a life-saving option for cirrhotic patients with complications and hepatocellular carcinoma.Despite the increasing number of liver transplants performed each year,the number of LT can... Liver transplantation(LT)provides a life-saving option for cirrhotic patients with complications and hepatocellular carcinoma.Despite the increasing number of liver transplants performed each year,the number of LT candidates on the waitlist remains unchanged due to an imbalance between donor organ supply and the demand which increases the waitlist time and mortality.Living donor liver transplant had a great role in increasing the donor pool and shortened waitlist time for LT candidates.Nevertheless,further strategies can be implemented to increase the pool of potential donors in deceased donor LT,such as reducing the rate of organ discards.Utilizing hepatitis C virus(HCV)seropositive liver grafts is one of the expanded donor organ criteria.A yearly increase of hundreds of transplants is anticipated as a result of maximizing the utilization of HCV-positive organs for HCV-negative recipients.Direct-acting antiviral therapy's efficacy has revolutionized the treatment of HCV infection and the use of HCV-seropositive donors in transplantation.The American Society of Transplantation advises against performing transplants from HCV-infected liver donors(D+)into HCV-negative recipient(R-)unless under Institutional Review Board-approved study rules and with full informed consent of the knowledge gaps associated with such transplants.Proper selection of patients to be transplanted with HCV-infected grafts and confirming their access to direct-acting antivirals if needed is im-portant.National and international consensuses are needed to regulate this process to ensure the maximum benefit and the least adverse events. 展开更多
关键词 Donor pool Hepatitis C-viremic organs Non-viremic organs Direct acting antivirals Hepatitis C virus treated Liver transplantation
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Formation and destruction processes of upper Sinian oil-gas pools in the Dingshan-Lintanchang structural belt, southeast Sichuan Basin, China 被引量:21
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作者 Liu Shugen Zhang Zhijing Huang Wenming Wang Guozhi Sun Wei Xu Guosheng Yuan Haifeng Zhang Changjun Deng Bin 《Petroleum Science》 SCIE CAS CSCD 2010年第3期289-301,共13页
The lower Cambrian Niutitang Formation hydrocarbon source rocks at the Dingshan- Lintanchang structure in the southeast Sichuan Basin were of medium-good quality with two excellent hydrocarbon-generating centers devel... The lower Cambrian Niutitang Formation hydrocarbon source rocks at the Dingshan- Lintanchang structure in the southeast Sichuan Basin were of medium-good quality with two excellent hydrocarbon-generating centers developed in the periphery areas, with a possibility of forming a medium to large-sized oil-gas field. Good reservoir rocks were the upper Sinian (Dengying Formation) dolomites. The mudstone in the lower Cambrian Niutitang Formation with a good sealing capacity was the cap rock. The widely occurring bitumen in the Dengying Formation indicates that a paleo oil pool was once formed in the study area. The first stage of paleo oil pool formation was maturation of the lower Cambrian source rocks during the late Ordovician. Hydrocarbon generation from the lower Cambrian source rocks stopped due to the Devonian-Carboniferous uplifting. The lower Cambrian source rocks then restarted generation of large quantities of hydrocarbons after deposition of the middle Permian sediments. This was the second stage of the paleo oil pool formation. The oil in the paleo oil pool began to crack during the late Triassic and a paleo gas pool was formed. This paleo gas pool was destroyed during the Yanshan-Himalayan folding, uplifting and denudation. Bitumen can be widely seen in the Dengying Formation in wells and outcrops in the Sichuan Basin and its periphery areas. This provides strong evidence that the Dengying Formation in the Sichuan Basin and its periphery areas was once an ultra-large structural-lithologic oil-gas field, which was damaged during the Yanshan-Himalayan period. 展开更多
关键词 SINIAN oil-gas pool Dingshan-Lintanchang structural belt Sichuan Basin
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Comparative studies on utilizing nitrogen capacity between two macroalgae Gracilaria tenuistipitata var. liui (rhodophyta) and Ulva pertusa (chlorophyta) II. Feedback controls of intracellular nitrogen pools on nitrogen uptake 被引量:5
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作者 LIU Jing Wen, DONG Shuang Lin (Aquaculture Research Laboratory, Ocean University of Qingdao, Qingdao 266003, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第3期323-327,共5页
The potential feedback by intracellular nitrogen pools on maximum N uptake (NH + 4) rate were determined for Gracilaria tenuistipitata var. liui and Ulva pertusa. The results of correlation matrix analyz... The potential feedback by intracellular nitrogen pools on maximum N uptake (NH + 4) rate were determined for Gracilaria tenuistipitata var. liui and Ulva pertusa. The results of correlation matrix analyzing showed that the surge uptake of ammonium seemed related to rapid changes in small intracellular pools of inorganic nitrogen or small peptide and amino acids rather than to changes in TN content of the macroalgae. The assimilation rates of nitrogen of U. pertusa and G. tenuistipitata increased slowly during N starvation and were mainly regulated by amino acids and some incorporation of amino acids into macromolecules. From ecological point of view, the fast growing and uptaking nutrient U. pertusa is more suitable to improve water quality in integrated shrimp culture ponds in which external nutrient supplies are usually high and constant during the culture period, while G. tenuistipitata var. liui is more suitable to be polycultured in a waters with intermittence supply of nutrients. 展开更多
关键词 nitrogen pools uptake kinetic MACROALGAE feedback
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New approach to eliminate structural redundancy in case resource pools using α mutual information 被引量:6
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作者 Man Xu Haiyan Yu Jiang Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第4期625-633,共9页
Structural redundancy elimination in case resource pools (CRP) is critical for avoiding performance bottlenecks and maintaining robust decision capabilities in cloud computing services. For these purposes, this pape... Structural redundancy elimination in case resource pools (CRP) is critical for avoiding performance bottlenecks and maintaining robust decision capabilities in cloud computing services. For these purposes, this paper proposes a novel approach to ensure redundancy elimination of a reasoning system in CRP. By using α entropy and mutual information, functional measures to eliminate redundancy of a system are developed with respect to a set of outputs. These measures help to distinguish both the optimal feature and the relations among the nodes in reasoning networks from the redundant ones with the elimination criterion. Based on the optimal feature and its harmonic weight, a model for knowledge reasoning in CRP (CRPKR) is built to complete the task of query matching, and the missing values are estimated with Bayesian networks. Moreover, the robustness of decisions is verified through parameter analyses. This approach is validated by the simulation with benchmark data sets using cloud SQL. Compared with several state-of-the-art techniques, the results show that the proposed approach has a good performance and boosts the robustness of decisions. 展开更多
关键词 case resource pool (CRP) knowledge reasoning redundancy elimination α mutual information robust decision.
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Effects of water and nitrogen addition on vegetation carbon pools in a semi-arid temperate steppe 被引量:2
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作者 Junqiang Jia Yunshe Dong +7 位作者 Yuchun Qi Qin Peng Xinchao Liu Liangjie Sun Shufang Guo Yunlong He Congcong Cao Zhongqing Yan 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第3期621-629,共9页
Global change will lead to increases in regional precipitation and nitrogen(N) deposition in the semi-arid grasslands of northern China. We investigated the responses of vegetation carbon(C) pools to simulated pre... Global change will lead to increases in regional precipitation and nitrogen(N) deposition in the semi-arid grasslands of northern China. We investigated the responses of vegetation carbon(C) pools to simulated precipitation and N deposition increases through field experiments in a typical steppe in Inner Mongolia. The treatments included NH4NO3 addition at concentrations of 0(CK), 5(LN, low nitrogen), 10(middle nitrogen, MN), and 20(HN,high nitrogen)(g m^(-2)a^(-1)) with and without water. After three consecutive years of treatment, from 2010 to 2012,water addition did not significantly change the size of the total vegetation C pools, but it significantly decreased the ratio of root:shoot(R:S)(P = 0.05) relative to controls. By contrast, N addition significantly increased the total vegetation C pools. The C pools in the LN, MN and HN treatments increased by 22, 39 and 44 %, respectively. MN produced the largest effect among the N concentrations,although differences between N-added treatments were not significant(P ? 0.05). N addition significantly reduced the ratio of root:shoot(R:S)(P = 0.03). However, there were no significant interactive effects of water and N addition on the vegetation C pools. 展开更多
关键词 Vegetationprecipitation NitrogenTemperate steppecarbon pools Increasingaddition Interactive effect
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Origin of Oils in“Subtle pools”in the Dongying Depression,Bohai Bay Basin, China 被引量:3
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作者 LI Sumei JIANG Zhengxue +2 位作者 LIU Keyu QIU Guiqiang GAO Yongjin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第1期184-196,共13页
Subtle traps or oil pools have become an important exploration play in the Dongying Depression, Bohai Bay Basin, east China. Despite recent successes in exploration, the formation mechanisms of subtle traps are still ... Subtle traps or oil pools have become an important exploration play in the Dongying Depression, Bohai Bay Basin, east China. Despite recent successes in exploration, the formation mechanisms of subtle traps are still not well understood. The majority of subtle oil pools in the Dongying Depression are developed in the middle interval of the Es3 Member of the Paleogene Shahejie Formation with the subtle traps being primarily of lenticular basin-floor turbidite sands encompassed in mudstones. Oil in the subtle traps was previously thought to have migrated directly from the surrounding source rocks of the same formation (Es3). Detailed geochemical investigation of 41 oils and 41 rock samples from the depression now indicates that the oils from the subtle traps cannot be correlated well with the surrounding Es3 source rocks, which are characterized by high Pr/ Ph (〉1), low Gammacerane/C30hopane, representing a freshwater lacustrine setting. In contrast the oils features low Pr/Ph (〈1) and relatively high Gammacerane content, showing a genetic affinity with the underlying Es4 source rocks, which also have the same qualities, indicating a brackish lacustrine setting. Oils in the Es3 subtle traps are probably derived from mixed sources with the contribution from the upper Es4 source rocks predominating. Therefore unconventional oil migration and accumulation mechanisms need to be invoked to explain the pooling of oils from the ES4 source rocks, which probably came through a thick low interval of the Es3 source rocks with no apparent structural or stratigraphic pathways. We suggest that the subtle oil migration pathway probably plays an important role here. This finding may have significant implications for future exploration and the remaining resource evaluation in the Dongying Depression. 展开更多
关键词 lenticular oil pools biomarkers oil-source rock correlation hydrocarbon migration and accumulation subtle oil migration pathway
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Quantitative prediction of mixed-source crude oils and its significance for understanding oil accumulation in subtle pools in the Dongying Depression,Bohai Bay Basin 被引量:2
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作者 Li Sumei Liu Keyu +4 位作者 Pang Xiongqi Li Maowen Jiang Zhenxue Qiu Guiqiang Gao Yongjin 《Petroleum Science》 SCIE CAS CSCD 2008年第3期203-211,共9页
Conventional geochemical approaches were utilized in the quantitative prediction of the proportions of mixed-source crude oils derived from the Es3 and ES4 members of the Paleogene Shahejie Formation. The mixed-source... Conventional geochemical approaches were utilized in the quantitative prediction of the proportions of mixed-source crude oils derived from the Es3 and ES4 members of the Paleogene Shahejie Formation. The mixed-source oils are accumulated in the middle interval of the Es3 member (Es3 M) in the Niuzhuang Sag, which is one of the sags where subtle traps are primarily of lenticular basin-floor turbidite sands within mudstones mostly developed in the Dongying Depression, Bohai Bay Basin. The result showed that about 18-92% of the mixed-source oils were derived from the Es4 source rocks with an average of 55-60%). Reservoirs associated with deep faults appear to have much more Es4 genetic affinity oils. A high proportion of the Es4-derived oils discovered in the Es3 M subtle lithological traps in the Niuzhuang Sag have long migration distances. This suggests that surrounding source rocks might not necessarily control the hydrocarbon supply for subtle traps. Subtle migration pathway may play an important role in the vertical oil migration. The traditional concept of hydrocarbons accumulation in these tenticular turbidite sandstone traps within a short migration distance from the surrounding source rocks is not supported by this study. The present result is also consistent with our previous findings that immature oils in the Bamianhe Oilfield in the south slope of the Niuzhuang Sag were actually mixed-source oils mostly sourced from the Es4 in the depocenter of the Niuzhuang Sag, and the petroleum potential of the ES4 member in the Dongying Depression should therefore be re-evaluated. 展开更多
关键词 Niuzhuang Sag lithological oil pool. mixed-source oil quantitative prediction
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A method for evaluating paleo hydrocarbon pools and predicting secondary reservoirs:a case study of the Sangonghe Formation in the Mosuowan area,Junggar Basin 被引量:2
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作者 Wei-Jiao Ma Yan-Zhao Wei Shi-Zhen Tao 《Petroleum Science》 SCIE CAS CSCD 2018年第2期252-269,共18页
Taking the Jurassic Sangonghe Formation in the Mosuowan-Mobei area of the Junggar Basin as an example, this paper provides a method that evaluates paleo hydrocarbon pools and predicts secondary reservoirs. Through Qua... Taking the Jurassic Sangonghe Formation in the Mosuowan-Mobei area of the Junggar Basin as an example, this paper provides a method that evaluates paleo hydrocarbon pools and predicts secondary reservoirs. Through Quantitative Grain Fluorescence (QGF) experiments, well-tie seismic correlation, and paleo structure analysis, the scale and distribution of paleo hydrocarbon pools in the study area are outlined. Combining current structural features and fault characteristics, the re-migration pathways of paleo oil and gas are depicted. Based on barrier conditions on the oil re-migration pathways and current reservoir distribution, we recognize three types of secondary reservoirs. By analyzing structural evolution and sand body-fault distribution, the major control factors of secondary reservoirs are specified and, consequently, favorable zones for secondary reservoirs are predicted. The results are mainly as follows. (1) In the primary accumulation period in the Cretaceous, paleo hydrocarbon pools were formed in the Sangonghe Formation of the Mosuowan uplift and their size and distribution were extensive and the exploration potential for secondary reservoirs should not be ignored. Besides, paleo reservoirs were also formed in the Mobei uplift, but just small scale. (2) In the adjustment period in the Neogene, traps were reshaped or destroyed and so were the paleo reservoirs, resulting in oil release. The released oil migrated linearly northward along the structural highs of the Mobei uplift and the Qianshao low-relief uplift and then formed secondary reservoirs when it met new traps. In this process, a structural ridge cooperated with sand bodies and faults, applying unobstructed pathways for oil and gas re-migration. (3) The secondary hydrocarbon pools are classified into three types: low-relief anticlinal type, lithologic pinch-out type and fault block type. The distribution of the first type is controlled by a residual low uplift in the north flank of the paleo-anticline. The second type is distributed in the lithologic pinch-out zones on the periphery of the inherited paleo uplift. The third type is controlled by fault zones of which the strikes are perpendicular to the hydrocarbon re-migration pathways. (4) Four favorable zones for secondary reservoirs are predicted: the low-relief structural zone of the north flank of the Mosuowan paleo-anticline, the fault barrier zone on the western flank of the Mobei uplift, the Qianshao low-relief uplift and the north area of the Mobei uplift that parallels the fault zone. The study above effectively supports the exploration of the Qianshao low-relief uplift, with commercial oil discovered in the Qianshaol well. Besides, the research process in this paper can also be applied to other basins to explore for secondary reservoirs. 展开更多
关键词 Junggar Basin Paleo hydrocarbon pools Hydrocarbon re-migration pathways Secondary reservoirs .Favorable zones
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Exploration Potential of Atectonic Oil-gas Pools in the Northern Shelf Basin of the South China Sea 被引量:1
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作者 ZhuWeilin WangZhenfeng LvMing 《Petroleum Science》 SCIE CAS CSCD 2004年第2期22-30,共9页
Large-scale oil exploration has been done and large quantities of oil-gas fields have been found in the northern shelf basin of the South China Sea for more than 20 years. The tectonic oil-gas pools are the main type.... Large-scale oil exploration has been done and large quantities of oil-gas fields have been found in the northern shelf basin of the South China Sea for more than 20 years. The tectonic oil-gas pools are the main type. With the exploration to be deepened, looking for atectonic oil-gas pools is listed in China's exploration strategy. There are advantages for the forming of atectonic oil-gas pools in the northern shelf basin of the South China Sea. Because the level of water has been frequently changing within all historical periods, lithozones are changed alternately in both vertical and lateral directions and formed lithologic deposition especially at low water level stages, such as the low-lying fans of basin-floor fans and slope fans. Due to frequent tectonic movement within all historical periods, many structural surfaces and structural unconformities were formed. At the same time, they also formed many kinds of structural unconformity oil-gas pools. According to our exploration and research, the promising areas of atectonic reservoirs within marine basins include: (1) the basin-floor fan of the deep water district, such as the central depression of the Southeast Qiong basin and Baiyun sag in the Zhujiangkou basin; (2) the frontal area of the large ancient delta, such as the Lingao structural belt in the Yingge Sea basin and Huizhou sag in the Zhujiangkou basin; (3) the unconformity pinchout belt or denudation belt in the slope area and the uplift area, for instance, the Yingdong slope belt in the Yingge Sea basin and Yacheng 13-1 structural belt in the southeast Qiong basin. All this proves that the prospects for atectonic oil-gas pools in the northern shelf basin of the South China Sea are very broad. 展开更多
关键词 Shelf basin atectonic oil-gas pool exploration potential
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Disinfection of swimming pools with chlorine and derivatives: formation of organochlorinated and organobrominated compounds and exposure of pool personnel and swimmers 被引量:2
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作者 Maria-Cristina Aprea Bruno Banchi +3 位作者 Liana Lunghini Massimo Pagliantini Antonio Peruzzi Gianfranco Sciarra 《Natural Science》 2010年第2期68-78,共11页
Chlorination of pool water leads to the forma-tion of many by-products, chloroform usually being the most abundant. The paper reports the results of a study evaluating exposure of bath-ers and pool employees to trihal... Chlorination of pool water leads to the forma-tion of many by-products, chloroform usually being the most abundant. The paper reports the results of a study evaluating exposure of bath-ers and pool employees to trihalomethanes (chloroform, bromodichloromethane, dibromo-chloromethane, bromoform) in four indoor swimming pools with chlorinated water. Chlo-roform concentrations in environmental air samples when the pool was in use (about 9 h), in the range 1-182 μg/m3, were greater near the pool than in the change rooms, passageways and offices. Chloroform concentrations in per-sonal air samples of pool employees were in the range 18-138 μg/m3. Urinary concentrations of chloroform averaged (geometric means) 0.123 and 0.165 μg/l and 0.404 and 0.342 μg/l prior and at the end of exposure during in water and out of water activities, respectively. The significant increase in urinary excretion of chloroform confirms that the source of the contaminant was pool water. Absorption of chloroform, estimated from airborne and water concentrations, was significantly correlated with delta chloroform (after/before exposure) and urinary concentra-tions of chloroform at the end of exposure. As chloroform is a toxic and possibly carcinogenic substance, these observations pose a problem principally for the general population of pool users. 展开更多
关键词 DISINFECTION By-Products Indoor SWIMMING pool TRIHALOMETHANES Biological Monitoring EXPOSURE Urine
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Soil carbon pools of six ecological regions of the United States 被引量:2
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作者 Amitava Chatterjee 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1933-1938,共6页
Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for p... Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for predicting change over time.Surface soil samples from six ecoregions of the United States were analyzed for permanganate oxidizable C(KMnO4-C)and mineralizable C pools.Variations of SOC ranged from 7.9 mg g^-1(Florida site)to 325 mg g^-1(Hawaii site).Mineralisable C pools and KMnO4-C were highest in soils from the Hawaii site.Mean annual precipitation explains SOC and resistant C pool variations.Clay content was related to mineralisable active C pools and bacterial abundance.Mean annual precipitation and clay content are potential variables for predicting changes in SOC pools at large spatial scales. 展开更多
关键词 Permanganate oxidizable carbon(KMnO4-C) Resistant carbon pool Mean residence time Soil carbon pools United States
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Effects of a decade of organic fertilizer substitution on vegetable yield and soil phosphorus pools, phosphatase activities, and the microbial community in a greenhouse vegetable production system 被引量:6
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作者 ZHANG Yin-jie GAO Wei +5 位作者 LUAN Hao-an TANG Ji-wei LI Ruo-nan LI Ming-yue ZHANG Huai-zhi HUANG Shao-wen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第7期2119-2133,共15页
Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated th... Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices. 展开更多
关键词 organic substitution management soil P pools phosphatase activity microbial community soil C/P PLS-PM
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Wintertime Stratospheric Anomalies-Part I: Warm Pools 被引量:2
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作者 Y.L.McHall 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期299-310,共12页
The stratospheric worm pools, called the 4-day wave also, are mainly the temperature anomalies in the polar regions of winter hemisphere. It will be shown that their occurrence, propagation speed and specific structur... The stratospheric worm pools, called the 4-day wave also, are mainly the temperature anomalies in the polar regions of winter hemisphere. It will be shown that their occurrence, propagation speed and specific structure can be explained by the lower frequency coherent heating resulting from the wave interaction in the breaking layers of the stratosphere. Although their vertical phase slope is negligibly small, the warm pools cannot be considered as a barotropic anomaly. 展开更多
关键词 Wintertime Stratospheric Anomalies-Part I Warm pools
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Effects of hypobaric hypoxia on adenine nucleotide pools,adenine nucleotide transporter activity and protein expression in rat liver 被引量:4
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作者 Cong-Yang Li Jun-Ze Liu +2 位作者 Li-Ping Wu Bing Li Li-Fen Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第13期2120-2124,共5页
瞄准:在老鼠肝在 mitochondrial 能代谢上探索比重低於脑脊髓液的组织缺氧的效果。方法:成年男 Wistar 老鼠暴露于高模仿 5,000 m 的一个比重低於脑脊髓液的房间为 23 h 的高度每天为 0 (H0 ) , 1 (H1 ) , 5 (H5 ) , 15 (H15 ) 并... 瞄准:在老鼠肝在 mitochondrial 能代谢上探索比重低於脑脊髓液的组织缺氧的效果。方法:成年男 Wistar 老鼠暴露于高模仿 5,000 m 的一个比重低於脑脊髓液的房间为 23 h 的高度每天为 0 (H0 ) , 1 (H1 ) , 5 (H5 ) , 15 (H15 ) 并且 30 d (H30 ) 分别地。老鼠被斩首杀头牺牲,肝被移开。肝线粒体被差示离心节目孤立。在织物和线粒体的腺嘌核苷酸水池(ATP,自动数据处理,和安培) 的尺寸被高效液相色谱法(HPLC ) 分开并且测量。腺嘌核苷酸 transporter (蚂蚁) 活动被同位素的技术决定。蚂蚁全部的蛋白质水平被西方的污点决定。结果:与 H0 组相比, intra-mitochondrial ATP 内容在所有组织缺氧组减少了。然而,当时, H5 组到达了最低的点(70.6%)(P【0.01 ) 与控制组相比。Intra-mitochondrial 自动数据处理和安培水平在所有组织缺氧组显示出类似的变化并且在 H0 组是比那显著地低的。另外, extra-mitochondrial ATP 和自动数据处理内容在所有组织缺氧组显著地减少了。而且,在组 H5, H15 和 H30 的 extra-mitochondrial 安培在 H0 组是比那显著地低的,而 H1 组不与控制状况相比标记变化。当时,在组织缺氧组的蚂蚁的活动显著地减少了,它在 H5 组(55.7%)(P【0.01 ) 是最低的与 H0 相比组。在 H30 组的蚂蚁活动比在 H15 组高,但是仍然在 H0 组比那降低。在 H5 的蚂蚁蛋白质水平, H15, H30 组,与 H0 相比,组显著地减少了,在 H5,组是它最低,在 H0 是那中的 27.1% 个组织(P【0.01 ) 。在 H30 组的蚂蚁蛋白质水平比在 H15 组高,但是仍然比在 H0 组降低。结论:比重低於脑脊髓液的组织缺氧减少 mitochondrial ATP 在老鼠肝满足,当 mitochondrial ATP 水平在长期的组织缺氧暴露期间恢复时。extra-mitochondrial ATP 的底层可能在组织缺氧暴露期间与蚂蚁活动的减少有关。 展开更多
关键词 低气压环境 低氧症 腺嘌呤核苷 基因表达 肝疾病
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Exploration Significance of Unconformity Structure on Subtle Pools
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作者 Kongyou Wu,Ming Zha,Jiangxiu Qu Faculty of Geo-Resource and Information,China University of Petroleum,Qingdao 266555,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期136-136,共1页
Vertical structure of an unconformity can be divided into three layers:basal conglomerate or transgressive sand,weathered clay layer and leached rock.When the weathered clay layer has a little thickness or limited dis... Vertical structure of an unconformity can be divided into three layers:basal conglomerate or transgressive sand,weathered clay layer and leached rock.When the weathered clay layer has a little thickness or limited distribution,the overlying and underlying strata will contact directly,and the lithology is often different.This lithologic difference causes different fluid transporting capacity,and it also 展开更多
关键词 UNCONFORMITY STRUCTURE subtle pools ACCUMULATION SIMULATION
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Characteristics of the main polluting trace elements in the water environment of mining subsidence pools 被引量:4
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作者 YAO En-qin GUI He-rong 《Journal of China University of Mining and Technology》 EI 2008年第3期362-367,共6页
Mining subsidence pools are water bodies formed by soil subsidence near mines. We studied the impact the surrounding coal production activities and power plants have on these waters by measuring the concentrations of ... Mining subsidence pools are water bodies formed by soil subsidence near mines. We studied the impact the surrounding coal production activities and power plants have on these waters by measuring the concentrations of harmful trace elements in these waters. The concentration of the four elements F, Hg, Se and As increased by 0.92%, 0.78%, 0.70% and 0.81%, respectively, in the Datong mining subsidence pool from November 2004 to November 2006. The four elements increased by 1.58%, 1.23%, 1.08% and 0.92%, respectively, in the Xie’er mining subsidence pool and 1.16%, 1.06%, 1.02% and 1.01%, respectively, in the Pansan mining subsidence pool over the same time period. The absolute levels of F, Hg, Se and As in the pool are related to the background levels of the elements. A close relationship between nearby coal mines and power plants and increasing levels of the measured elements is noted. 展开更多
关键词 水环境 煤矿 微量元素 矿穴沉陷池
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Forest and Soil Carbon Stocks, Pools and Dynamics and Potential Climate Change Mitigation in Nepal 被引量:1
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作者 Shrestha Him Lal Roshan M. Bajracharya Bishal K. Sitaula 《Journal of Environmental Science and Engineering(B)》 2012年第6期800-811,共12页
关键词 土壤碳储量 森林砍伐 气候变化 尼泊尔 土地利用变化 地理信息技术 碳排放量 地理信息系统
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Sri Lanka seasonal warm pools
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作者 Guoqing HAN Changming DONG +1 位作者 Jingsong YANG Yu LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第2期437-446,共10页
Sri Lanka seasonal warm pools(SSWPs)with high sea surface temperature(SST)(greater than 29.6℃in summer and greater than 28℃in winter)around the Sri Lanka Island are discovered using 37-year(1982–2018)satellite remo... Sri Lanka seasonal warm pools(SSWPs)with high sea surface temperature(SST)(greater than 29.6℃in summer and greater than 28℃in winter)around the Sri Lanka Island are discovered using 37-year(1982–2018)satellite remote sensing SST data.It is identifi ed that during the onset of the summer(winter)monsoon,the maximum SST in the SSWPs can be 1.8℃(0.8℃)higher than the surrounding ocean.Due to orographic infl uences,the wind intensity on the leeward side of Sri Lanka is weakened,reducing evaporation and oceanic mixing,and resulting in higher SST.The analysis of the long-term data shows that SSWPs are related to El Niño-Southern Oscillation(ENSO)events.Background currents are also found to play important roles in governing the SSWPs intensities through the heat advection. 展开更多
关键词 Sri Lanka MONSOON warm pool
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