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Excess pore pressure behavior and evolution in deep coalbed methane reservoirs
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作者 Changqing Liu Zhaobiao Yang +3 位作者 Yong Qin Xia Yan Yunhai Wang Zhe Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期763-781,共19页
Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these reservoirs.While some prod... Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these reservoirs.While some production data analysis techniques have been adapted from conventional oil and gas wells,there remains a gap in the understanding of pore pressure generation and evolution,particularly in wells subjected to large-scale hydraulic fracturing.To address this gap,a novel technique called excess pore pressure analysis(EPPA)has been introduced to the coal seam gas industry for the first time to our knowledge,which employs dual-phase flow principles based on consolidation theory.This technique focuses on the generation and dissipation for excess pore-water pressure(EPWP)and excess pore-gas pressure(EPGP)in stimulated deep coal reservoirs.Equations have been developed respectively and numerical solutions have been provided using the finite element method(FEM).Application of this model to a representative field example reveals that excess pore pressure arises from rapid loading,with overburden weight transferred under undrained condition due to intense hydraulic fracturing,which significantly redistributes the weight-bearing role from the solid coal structure to the injected fluid and liberated gas within artificial pores over a brief timespan.Furthermore,field application indicates that the dissipation of EPWP and EPGP can be actually considered as the process of well production,where methane and water are extracted from deep coalbed methane wells,leading to consolidation for the artificial reservoirs.Moreover,history matching results demonstrate that the excess-pressure model established in this study provides a better explanation for the declining trends observed in both gas and water production curves,compared to conventional practices in coalbed methane reservoir engineering and petroleum engineering.This research not only enhances the understanding of DCBM reservoir behavior but also offers insights applicable to production analysis in other unconventional resources reliant on hydraulic fracturing. 展开更多
关键词 Deep coalbed methane CONSOLIDATION excess pore-water pressure excess pore-gas pressure Production data analysis
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Excess non-COVID-19-related mortality among inflammatory bowel disease decedents during the COVID-19 pandemic 被引量:1
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作者 Sarah Rotondo-Trivette Xin-Yuan He +9 位作者 Jamil S Samaan Fan Lv Emily Truong Michaela Juels Anthony Nguyen Xu Gao Jian Zu Yee Hui Yeo Fan-Pu Ji Gil Y Melmed 《World Journal of Gastroenterology》 SCIE CAS 2024年第20期2677-2688,共12页
BACKGROUND The coronavirus disease 2019(COVID-19)pandemic disrupted healthcare in the United States.AIM To investigate COVID-19-related and non-COVID-19-related death and characteristics associated with excess death a... BACKGROUND The coronavirus disease 2019(COVID-19)pandemic disrupted healthcare in the United States.AIM To investigate COVID-19-related and non-COVID-19-related death and characteristics associated with excess death among inflammatory bowel disease(IBD)decedents.METHODS We performed a register-based study using data from the National Vital Statistics System,which reports death data from over 99%of the United States population,from January 1,2006 through December 31,2021.IBD-related deaths among adults 25 years and older were stratified by age,sex,race/ethnicity,place of death,and primary cause of death.Predicted and actual age-standardized mortality rates(ASMRs)per 100000 persons were compared.RESULTS 49782 IBD-related deaths occurred during the study period.Non-COVID-19-related deaths increased by 13.14%in 2020 and 18.12%in 2021[2020 ASMR:1.55 actual vs 1.37 predicted,95%confidence interval(CI):1.26-1.49;2021 ASMR:1.63 actual vs 1.38 predicted,95%CI:1.26-1.49].In 2020,non-COVID-19-related mortality increased by 17.65%in ulcerative colitis(UC)patients between the ages of 25 and 65 and 36.36%in non-Hispanic black(NHB)Crohn’s disease(CD)patients.During the pandemic,deaths at home or on arrival and at medical facilities as well as deaths due to neoplasms also increased.CONCLUSION IBD patients suffered excess non-COVID-19-related death during the pandemic.Excess death was associated with younger age among UC patients,and with NHB race among CD patients.Increased death at home or on arrival and due to neoplasms suggests that delayed presentation and difficulty accessing healthcare may have led to increased IBD mortality. 展开更多
关键词 Inflammatory bowel disease Ulcerative colitis Crohn’s disease COVID-19 excess death Race SEX DISPARITIES
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Density of excess modes below the first phonon mode in four-dimensional glasses
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作者 王利近 胥鼎 张世允 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期483-489,共7页
Glasses are known to possess low-frequency excess modes beyond the Debye prediction.For decades,it has been assumed that evolution of low-frequency density of excess modes D(ω) with frequency ω follows a power-law s... Glasses are known to possess low-frequency excess modes beyond the Debye prediction.For decades,it has been assumed that evolution of low-frequency density of excess modes D(ω) with frequency ω follows a power-law scaling:D(ω)~ω~γ.However,it remains debated on the value of γ at low frequencies below the first phonon-like mode in finitesize glasses.Early simulation studies reported γ=4 at low frequencies in two-(2D),three-(3D),and four-dimensional(4D)glasses,whereas recent observations in 2D and 3D glasses suggested γ=3.5 in a lower-frequency regime.It is uncertain whether the low-frequency scaling of D(ω)~ω^(3.5) could be generalized to 4D glasses.Here,we conduct numerical simulation studies of excess modes at frequencies below the first phonon-like mode in 4D model glasses.It is found that the system size dependence of D(ω) below the first phonon-like mode varies with spatial dimensions:D(ω) increases in2D glasses but decreases in 3D and 4D glasses as the system size increases.Furthermore,we demonstrate that the ω^(3.5)scaling,rather than the ω~4 scaling,works in the lowest-frequency regime accessed in 4D glasses,regardless of interaction potentials and system sizes examined.Therefore,our findings in 4D glasses,combined with previous results in 2D and 3D glasses,suggest a common low-frequency scaling of D(ω)~ ω^3.5) below the first phonon-like mode across different spatial dimensions,which would inspire further theoretical studies. 展开更多
关键词 vibrational density of states excess modes four-dimensional glasses SCALING computer simulation
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Point-of-care ultrasonography spotlight:Could venous excess ultrasound serve as a shared language for internists and intensivists?
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作者 Anosh Aslam Khan Hasham Saeed +3 位作者 Ibtehaj Ul Haque Ayman Iqbal Doantrang Du Abhilash Koratala 《World Journal of Critical Care Medicine》 2024年第2期126-136,共11页
Point-of-care ultrasonography(POCUS),particularly venous excess ultrasound(VExUS)is emerging as a valuable bedside tool to gain real-time hemodynamic insights.This modality,derived from hepatic vein,portal vein,and in... Point-of-care ultrasonography(POCUS),particularly venous excess ultrasound(VExUS)is emerging as a valuable bedside tool to gain real-time hemodynamic insights.This modality,derived from hepatic vein,portal vein,and intrarenal vessel Doppler patterns,offers a scoring system for dynamic venous congestion assessment.Such an assessment can be crucial in effective management of patients with heart failure exacerbation.It facilitates diagnosis,quantification of congestion,prognostication,and monitoring the efficacy of decongestive therapy.As such,it can effectively help to manage cardiorenal syndromes in various clinical settings.Extended or eVExUS explores additional veins,potentially broadening its applications.While VExUS demonstrates promising outcomes,challenges persist,particularly in cases involving renal and liver parenchymal disease,arrhythmias,and situations of pressure and volume overload overlap.Proficiency in utilizing spectral Doppler is pivotal for clinicians to effectively employ this tool.Hence,the integration of POCUS,especially advanced applications like VExUS,into routine clinical practice necessitates enhanced training across medical specialties. 展开更多
关键词 Point-of-care ultrasonography ULTRASOUND Venous excess ultrasound Doppler Congestion Heart failure
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Orthodontic-surgical treatment for severe skeletal class Ⅱ malocclusion with vertical maxillary excess and four premolars extraction: A case report 被引量:2
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作者 Yi-Wen Zhou Yan-Yi Wang +3 位作者 Zhi-Feng He Ming-Xing Lu Gui-Feng Li Huang Li 《World Journal of Clinical Cases》 SCIE 2023年第5期1106-1114,共9页
BACKGROUND Patient satisfaction with facial appearance at the end of orthodontic camouflage treatment is very important, especially for skeletal malocclusion. This case report highlights the importance of the treatmen... BACKGROUND Patient satisfaction with facial appearance at the end of orthodontic camouflage treatment is very important, especially for skeletal malocclusion. This case report highlights the importance of the treatment plan for a patient initially treated with four-premolar-extraction camouflage, despite indications for orthognathic surgery.CASE SUMMARY A 23-year-old male sought treatment complaining about his unsatisfactory facial appearance. His maxillary first premolars and mandibular second premolars had been extracted, and a fixed appliance had been used to retract his anterior teeth for two years without improvement. He had a convex profile, a gummy smile, lip incompetence, inadequate maxillary incisor inclination, and almost a class I molar relationship. Cephalometric analysis showed severe skeletal class Ⅱ malocclusion(A point-nasion-B point = 11.5°) with a retrognathic mandible(sella-nasion-B point = 75.9°), a protruded maxilla(sella-nasion-A point = 87.4°), and vertical maxillary excess(upper incisor to palatal plane = 33.2 mm). The excessive lingual inclination of the maxillary incisors(upper incisor to nasion-A point line =-5.5°)was due to previous treatment attempts to compensate for the skeletal class Ⅱ malocclusion. The patient was successfully retreated with decompensating orthodontic treatment combined with orthognathic surgery. The maxillary incisors were repositioned and proclined in the alveolar bone, the overjet was increased, and a space was created for orthognathic surgery, including maxillary impaction, anterior maxillary back-setting, and bilateral sagittal split ramus osteotomy to correct his skeletal anteroposterior discrepancy. Gingival display was reduced, and lip competence was restored. In addition, the results remained stable after 2 years. The patient was satisfied with his new profile as well as with the functional malocclusion at the end of treatment.CONCLUSION This case report provides orthodontists a good example of how to treat an adult with severe skeletal class Ⅱ malocclusion with vertical maxillary excess after an unsatisfactory orthodontic camouflage treatment. Orthodontic and orthognathic treatment can significantly correct a patient’s facial appearance. 展开更多
关键词 Case report Skeletal classⅡmalocclusion Vertical excess Gummy smile Camouflage treatment Orthognathic surgery
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Managing excess PbI_(2)for efficient perovskite solar cells 被引量:1
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作者 Xiaodong Li Jie Sun +2 位作者 Bozhang Li Junfeng Fang Liming Ding 《Journal of Semiconductors》 EI CAS CSCD 2023年第8期7-9,共3页
Perovskite solar cells(PSCs)have attracted much attention due to their low cost,high efficiency and easy processing.Recently,You et al.achieved a record efficiency of 26.1%(certified 25.6%)in PSCs with excellent stabi... Perovskite solar cells(PSCs)have attracted much attention due to their low cost,high efficiency and easy processing.Recently,You et al.achieved a record efficiency of 26.1%(certified 25.6%)in PSCs with excellent stability[1].Excess PbI_(2) in perovskite films was converted into inactive(PbI_(2))2RbCl to avoid its detrimental effect to device stability,while maintaining its positive effect to device efficiency. 展开更多
关键词 PEROVSKITE STABILITY excess
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Preliminary Study on the Treatment Efficiency of Pasteurized Lime Thermal Alkaline Hydrolysis for Excess Activated Sludge and Reduction of Tetracycline Resistance Genes
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作者 Maoxia Chen Qixuan Zhou +3 位作者 Jiayue Zhang Jiaoyang Li Wei Zhang Huan Liu 《Journal of Renewable Materials》 EI 2023年第10期3711-3723,共13页
Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in thi... Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in this study to improve the efficiency of pretreatment method.Direct thermal hydrolysis(TH),pasteurized thermal hydrolysis(PTH),and alkaline pasteurized thermal hydrolysis(PTH+CaO and PTH+NaOH)methods were used to treat EAS.Each method was compared and analyzed in terms of dissolution in ammonium nitrogen(NH_(4)^(+)-N)and soluble COD(SCOD)in EAS.Furthermore,the removal of tetracycline resistance genes(TRGs)and class 1 transposon gene intI1 from EAS was investigated.The NH_(4)^(+)-N and SCOD concentrations in EAS treated by PTH were 1.24 and 2.58 times higher than those of TH.However,the removal efficiency of total TRGs and intI1 between the groups was comparable.The SCOD concentration of the PTH+NaOH group was 4.37 times higher than that of the PTH group,and the removal efficiency of total TRGs was increased by 9.52%compared with that by PTH.The NH_(4)^(+)-N and SCOD concentrations of the PTH+CaO group could reach 85.04%and 92.14%of the PTH+NaOH group,but the removal efficiency of total TRGs by PTH+CaO was 19.78%lower than that by PTH+NaOH.Thus,to reduce the financial cost in actual operation,lime(CaO)can be used instead of a strong alkali(NaOH),and pasteurized steam at 70℃ instead of conventional high-temperature heating to treat EAS.This study provides a reference for the development of alkaline hydrolysis under moderate temperatures along with the removal of TRGs in EAS. 展开更多
关键词 excess activated sludge tetracycline resistance genes thermal alkaline hydrolysis LIME pasteurized thermal hydrolysis
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Safety Evaluations of Long-Term and Excessive Intakes of Bifidobacterium longum CLA8013: A Placebo-Controlled, Randomized, Double-Blind Study
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作者 Daisuke Takami Keisuke Okada +3 位作者 Yutaka Makizaki Yoshiki Tanaka Hiroshi Ohno Daisuke Tsuge 《Food and Nutrition Sciences》 2023年第10期997-1012,共16页
Heat-killed Bifidobacterium longum CLA8013 has been demonstrated to improve the frequency of defecation, straining, and pain during defecation in human placebo-controlled, double-blind, parallel-group studies. We cond... Heat-killed Bifidobacterium longum CLA8013 has been demonstrated to improve the frequency of defecation, straining, and pain during defecation in human placebo-controlled, double-blind, parallel-group studies. We conducted a randomized, double-blind, placebo-controlled, parallel-group study to evaluate the safety of both long-term and excessive intakes of heat-killed B. longum CLA8013, when used as a food with functional claims. In both tests, 30 healthy volunteers were divided into two groups: an active group that ingested heat-killed B. longum CLA8013 and a placebo group. In the long-term intake safety study, participants in the active group ingested 25 billion cells/day for 12 weeks. In the excessive intake safety study, participants in the active group ingested 125 billion cells/day for 4 weeks. Physical, hematological, biochemical, and urine examinations were conducted, and adverse events were evaluated in both studies. The studies revealed no abnormalities in any of the safety tests. In conclusion, no safety-related issues were identified with long-term or excessive intake of heat-killed B. longum CLA8013. 展开更多
关键词 CONSTIPATION SAFETY Bifidobacterium longum LONG-TERM excessIVE
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Pyloric Stenosis and Nonbilious Vomiting in Infants: Negative Base Excess and Hypercapnia—Two Opposing Points of One Scale a Comparative Case Series
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作者 Ralf-Bodo Tröbs Tomasz Baranski +1 位作者 Andreas Lipphaus Matthias Nissen 《Open Journal of Pediatrics》 CAS 2023年第1期104-112,共9页
Background: Blood pH and bicarbonate estimations are basal acid-base laboratory tests that are performed in infants with infantile hypertrophic pyloric stenosis (IHPS). This study aimed to define the clinical value of... Background: Blood pH and bicarbonate estimations are basal acid-base laboratory tests that are performed in infants with infantile hypertrophic pyloric stenosis (IHPS). This study aimed to define the clinical value of pCO<sub>2</sub> and BE in infants suspected to have IHPS. Methods: We collected data from 80 “surgical” infants younger than 100 days with prolonged nonbilious vomiting who were suspected to have IHPS. In 65 infants, pyloric stenosis was confirmed, and 15 infants had nonsurgical conditions. Capillary blood was tested for standard acid-base parameters and lactate. The two groups were compared. Results: Eighty-eight percent of the IHPS infants had elevated standard bicarbonate levels (st bicarb) > 25 mmol/l, and 60% had BE > 3.5 mmol/l;12% of the infants showed hypercapnia (pCO<sub>2</sub> ≥ 50 mmHg) associated with markedly increased standard bicarbonate and BE. Infants with nonsurgical vomiting were older at admission (p = 0.002), had a longer duration of vomiting (p < 0.001), were older (p = 0.002) and weighted more at admission (p = 0.004), had lower pCO<sub>2</sub> (p = 0.021), lower st bicarb (p < 0.001) and lower BE (p = 0.001). In addition, nonsurgical infants showed a trend to anemia (p = 0.002). Conclusions: In infants with IHPS/nonbilious vomiting, acid-base analysis (ABA) is equivocal or inconclusive. These findings may be misleading and could result in a false clinical decision. Nonsurgical vomiting is associated with a lower degree of alkalosis, normocapnia to slight hypercapnia and a base deficit. However, even infants with IHPS may present with a negative BE. In infants with IHPS and severe alkalosis, hypercapnia carries a risk for respiratory depression. Monitoring the infant’s respiration allows for the early detection of respiratory deterioration. 展开更多
关键词 Pyloric Stenosis Nonbilious Vomiting HYPOVENTILATION Base excess HYPERCAPNIA
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Abnormal expression and significance of circ-CBLB/miR-486-5p in patients with rheumatoid arthritis of spleen deficiency and dampness excess type
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作者 LI Shu WAN Lei +5 位作者 LIU Jian HUANG Chuan-bing CHEN Ying-ying LI Fang-ze HU Sai-sai CHENG Jing 《Journal of Hainan Medical University》 CAS 2023年第17期43-49,共7页
Objective:To explore the abnormal expression and significance of circ-CBLB/miR-486-5p in patients with rheumatoid arthritis of spleen deficiency and dampness excess type.Methods:The 30 healthy individuals included in ... Objective:To explore the abnormal expression and significance of circ-CBLB/miR-486-5p in patients with rheumatoid arthritis of spleen deficiency and dampness excess type.Methods:The 30 healthy individuals included in the method were from the Physical Examination Center of Anhui Provincial Hospital of Traditional Chinese Medicine,and the 60 rheumatoid arthritis patients included were from the First Affiliated Hospital of Anhui University of Traditional Chinese Medicine.The disease activity score of patients with rheumatoid arthritis was evaluated using VAS score and DAS28 score,joint symptoms and spleen deficiency syndrome score were evaluated using graded quantification method,immune inflammation indicators were detected using relevant instruments,inflammatory cytokines were detected using ELISA method,macrophage markers were detected using FCM method,and pathway gene expression was detected using RT-qPCR;Evaluate the predictive effect of circ-CBLB and miR-486-5p on disease activity in rheumatoid arthritis using ROC curves.Results:(1)miR-486-5p,CD14^(+)CD86^(+),ESR,CRP,RF,Anti CCP Ab,IL-6,TNF in patients with rheumatoid arthritis-αThe levels of circ-CBLB,CD14^(+)CD163^(+),IL-4,and IL-10 were significantly higher than those of healthy individuals;(2)The expression level of circ-CBLB in patients with rheumatoid arthritis is positively correlated with CD14^(+)CD163^(+),and negatively correlated with miR-486-5p and CD14^(+)CD86^(+);The expression level of miR-486-5p is negatively correlated with CD14^(+)CD163^(+)and positively correlated with CD14^(+)CD86^(+);There is a negative correlation between CD14^(+)CD86^(+)and CD14^(+)CD163^(+);ESR is negatively correlated with circ-CBLB,and positively correlated with miR-486-5p,CD14^(+)CD86^(+),CRP;CRP is negatively correlated with circ-CBLB,CD14^(+)CD163^(+),and positively correlated with CD14^(+)CD86^(+),ESR;(3)The expression level of circ-CBLB in patients with rheumatoid arthritis is negatively correlated with joint tenderness,morning stiffness,lack of qi and lazy speech,and postprandial abdominal distension score;The expression level of miR-486-5p is positively correlated with the scores of joint tenderness and decreased appetite.(4)The ROC curve shows that in terms of circ-CBLB,ESR,CRP,VAS,and DAS28 AUC are 0.662(P=0.032),0.658(P=0.035),0.516(P=0.830),and 0.791(P=0.000),respectively.In terms of miR-486-5p,ESR,CRP,VAS,and DAS28 AUC were 0.566(P=0.385),0.511(P=0.883),0.592(P=0.223),and 0.727(P=0.003),respectively.Conclusion:The abnormal expression of circ CBLB and miR-486-5p in peripheral blood mononuclear cell of patients with rheumatoid arthritis of spleen deficiency and dampness excess type is related to inflammatory polarization markers,immune inflammation,disease activity,joint symptoms and spleen deficiency syndrome of rheumatoid arthritis,and the low expression of circ CBLB and high expression of miR-486-5p have certain predictive value for disease activity of rheumatoid arthritis. 展开更多
关键词 Rheumatoid arthritis circ-CBLB MiR-486-5p Inflammatory polarization Spleen deficiency and dampness excess syndrome
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小Excess与开流形的拓扑(英文) 被引量:4
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作者 徐森林 王作勤 杨芳云 《应用数学》 CSCD 北大核心 2002年第4期7-12,共6页
本文中 ,我们应用比较几何的方法研究开流形的Excess与其拓扑之间的关系 .我们证明了对于一个曲率下有界的开流形 ,当它的Excess被其临界半径的某个函数所界定时 ,它就有有限拓扑型或微分同胚于n维z欧氏空间 .
关键词 excess函数 开流形 有限拓扑型 临界点 比较定理
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Impacts of Excessive Soaking on N, P, and K in Substrates Plots and Seedling Growth
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作者 王甲辰 左强 +4 位作者 谷佳林 肖强 邹国元 张琳 王美菊 《Agricultural Science & Technology》 CAS 2012年第1期158-161,180,共5页
[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Dispos... [Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Disposable excessive soak- ing and regression relation of nutrition infusion of substrate plots were studied by design of 13 time gradient. Plant nutrition absorption and growth effects after sub- strate plots immersed by water were investigated by growing tomato. [Result] Con- centration and time of the three nutrition immersed in water had the regression equation of each, as follows: N=-2E-05t2+0.016 lt+2.0553, P=0.002 2t+2.248 5 and K=0.004 7t+0.875 8. With nutrition loss of the three, however, loss amount was al- most same with variance analysis of regression equation, which may result from its volatilization. Regression equations of P and K were: P=0.125 7t-0.117, and K=0.022 5t.1514, which led to adverse impact on plant absorption of N and K above ground, whose equations were N=20.64e-4E-0.4t, and K=E-06t2-0.011 3t+29.055. Meanwhile, un- der the condition, sound seedling index was not impacted a lot by excessive immer- sion. [Conclusion] This study has provided theoretical reference for guidance of sub- strate plot soaking method, cultivation and regulation, and breeding, as well as agri- cultural production. 展开更多
关键词 Substrate plot Saturation and expansion for absorption excessive water Regression equation
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Excess函数的应用(英文)
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作者 徐森林 邓勤涛 《应用数学》 CSCD 北大核心 2007年第1期1-5,共5页
在本文中,我们研究了曲率有下界的开流形的拓扑,并推广了文[7]中的结果,证明了截曲率有下界的开流形如果它的excess函数被它的临界半径的某个函数所界定时,它就具有有限拓扑型或者微分同胚于Rn.
关键词 excess函数 有限拓扑型 临界点 比较定理
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Treating both wastewater and excess sludge with an innovative process
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作者 HE Sheng-bing, WANG Bao-zhen, WANG Lin, JIANG Yi-feng (School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第6期749-756,共8页
The innovative process consists of biological unit for wastewater treatment and ozonation unit for excess sludge treatment. An aerobic membrane bioreactor(MBR) was used to remove organics and nitrogen, and an anaerobi... The innovative process consists of biological unit for wastewater treatment and ozonation unit for excess sludge treatment. An aerobic membrane bioreactor(MBR) was used to remove organics and nitrogen, and an anaerobic reactor was added to the biological unit for the release of phosphorus contained at aerobic sludge to enhance the removal of phosphorus. For the excess sludge produced in the MBR, which was fed to ozone contact column and reacted with ozone, then the ozonated sludge was returned to the MBR for further biological treatment. Experimental results showed that this process could remove organics, nitrogen and phosphorus efficiently, and the removals for COD, NH 3-N, TN and TP were 93.17%, 97.57%, 82.77% and 79.5%, respectively. Batch test indicated that the specific nitrification rate and specific denitrification rate of the MBR were 1.03 mg NH 3-N/(gMLSS·h) and 0.56 mg NOx-N/(gMLSS·h), and denitrification seems to be the rate-limiting step. Under the test conditions, the sludge concentration in the MBR was kept at 5000—6000 mg/L, and the wasted sludge was ozonated at an ozone dosage of 0.10 kgO 3/kgSS. During the experimental period of two months, no excess sludge was wasted, and a zero withdrawal of excess sludge was implemented. Through economic analysis, it was found that an additional ozonation operating cost for treatment of both wastewater and excess sludge was only 0.045 RMB Yuan(USD 0.0054)/m 3 wastewater. 展开更多
关键词 wastewater treatment excess sludge aerobic membrane bioreactor(MBR) anaerobic reactor OZONATION zero withdrawal of excess sludge
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Releasing characteristics of phosphorus and other substances during thermal treatment of excess sludge 被引量:26
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作者 XUE Tao HUANG Xia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第10期1153-1158,共6页
The releasing characteristics of phosphorus, nitrogen compounds, organics, and some metal cations during thermal treatment of excess sludge were investigated. It was found that during heating not only phosphorus, but ... The releasing characteristics of phosphorus, nitrogen compounds, organics, and some metal cations during thermal treatment of excess sludge were investigated. It was found that during heating not only phosphorus, but also nitrogen compounds, organics, and some metal cations could be released in abundance. The maximum orthophosphate (ortho-P) release of about 90 mg/L in concentration was observed at 50℃ in 1 h. Except for volatile fatty acids (VFAs), comparatively little total nitrogen (TN), total organic carbon (TOC), and metal cations were released at the same time. Such results might favor further process of phosphorus recovery. VFAs were considerably released only at 50℃. Acetic, butyric, and propionic acid were the most abundant components in turn and their releasing profiles exhibited good linear relationship with time (R2 = 0.9977, 0.9624, and 0.8908, respectively). The concentrations of Mg^2+ and K^+ increased with time and temperature during thermal treatment, but Ca^2+ decreased. The release of Mg^2+ and K^+ agreed well with TP release (R^2 = 0.9892 and 0.9476, respectively). Temperature in the experimental range had very little impact on the linear relationships, especially of Mg^2+. Moreover, the parameter of mixed liquor suspended solids (MLSS) was found to be an important factor for thermal sludge treatment as the released ortho-P and total phosphorus (TP) at 50℃ increased more than one-fold when MLSS was increased from 4000 to 8000 mg/L. 展开更多
关键词 phosphorus recovery excess sludge volatile fatty acids (VFAs) metal cations
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Effects of Exogenous Silicon on Photosynthetic Capacity and Antioxidant Enzyme Activities in Chloroplast of Cucumber Seedlings Under Excess Manganese 被引量:14
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作者 FENG Jian-peng SHI Qing-hua WANG Xiu-feng 《Agricultural Sciences in China》 CAS CSCD 2009年第1期40-50,共11页
Effects of silicon on photosynthetic parameters and antioxidant enzymes of chloroplast in cucumber seedlings under excess Mn were studied. Compared with the control, excess Mn significantly inhibited net photosyntheti... Effects of silicon on photosynthetic parameters and antioxidant enzymes of chloroplast in cucumber seedlings under excess Mn were studied. Compared with the control, excess Mn significantly inhibited net photosynthetic rate (Pn), stomatal conductance, as well as the maximum yield of the photosystem II photochemical reactions (Fv/Fm) and the quantum yield of photosysytem II electron transport (Φ PSII), application of Si reversed the negative effects of excess Mn. In the further investigation, it was obtained that application of Si significantly increased the activities of enzymes related with ascorbate-glutathione cycle including ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) in cucumber chloroplast under excess Mn, this could be responsible for the lower accumulation of H2O2 and lower lipid peroxidation of chloroplast induced by Mn, and resulted in keeping higher photosynthesis. 展开更多
关键词 CUCUMBER excess manganese photosynthesis chlorophyll fluorescence CHLOROPLAST antioxidant enzymes
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Updates on the relation of weight excess and reproductive function in men: sleep apnea as a new area of interest 被引量:11
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作者 Ahmad O Hammoud Douglas T Carrell +2 位作者 Mark Gibson C Matthew Peterson A Wayne Meikle 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第1期77-81,176,177,共7页
Obesity has a negative effect on male reproductive function. It is associated with low testosterone levels and alteration in gonadotropin secretion. Male obesity has been linked to reduced male fertility. Data regardi... Obesity has a negative effect on male reproductive function. It is associated with low testosterone levels and alteration in gonadotropin secretion. Male obesity has been linked to reduced male fertility. Data regarding the relation of obesity to sperm parameters are conflicting in terms of the nature and magnitude of the effect. New areas of interest are emerging that can help explain the variation in study results, such as genetic polymorphism and sleep apnea. Sleep disorders have been linked to altered testosterone production and hypogonadism in men. It was also correlated to erectile dysfunction. The relation of sleep disorders to male fertility and sperm parameters remains to be investigated. Men with hypogonadism and infertility should be screened for sleep apnea. Treatment of obesity and sleep apnea improves testosterone levels and erectile function. 展开更多
关键词 INFERTILITY male infertility reproductive function sleep apnea weight excess
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A novel approach to treat combined domestic wastewater and excess sludge in MBR 被引量:6
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作者 HE Sheng bing, WANG Bao zhen, WANG Lin, JIANG Yi feng, ZHANG Li\|qiu (School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第5期674-679,共6页
Domestic wastewater was treated by combined anaerobic biofilm aerobic membrane bioreactor(MBR) process, and part biomass in MBR was withdrawn to treat with ozone, then the ozonated sludge was returned to anaerobic in... Domestic wastewater was treated by combined anaerobic biofilm aerobic membrane bioreactor(MBR) process, and part biomass in MBR was withdrawn to treat with ozone, then the ozonated sludge was returned to anaerobic inlet. In aerobic MBR, MLSS and DO were controlled at 3000—3500 mg/L and 0 8 mg/L respectively. Comparing the experimental results of two stages, it was noticed that ozonation did not affect the removal efficiency for organics but had a significant influence on the removals of NH 3 N and TN. During the ozonation period of two months, no excess sludge was wasted, and a zero sludge yield was obtained. 展开更多
关键词 combined anaerobic biofilm aerobic membrane(MBR) domestic wastewater OZONATION excess sludge sludge yield
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Excess函数的性质及其应用 被引量:1
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作者 巩军胜 《甘肃科学学报》 2008年第4期23-25,共3页
证明了Ric(M)≥-(n-1)完备非紧的n维黎曼流形M,若其上某一点的Excess函数有上界(常数)时,M就具有有限拓扑型或微分同胚于Rn.
关键词 RICCI曲率 excess函数 有限拓扑型 微分同胚
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Effect of Selenium Supplementation on Activity and mRNA Expression of Type 1 Deiodinase in Mice With Excessive Iodine Intake 被引量:5
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作者 XUE-FENG YANG XIAO-HUI HOU JIAN XW HUAI-LAN GUO CHEN-JIANG YING XIAO-YI CHEN XIU-FA SUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2006年第4期302-308,共7页
Objective To investigate the effect of selenium supplementation on the selenium status and selenoenzyme, especially the activity and mRNA expression of type 1 deiodinase (D1) in mice with excessive iodine (EI) int... Objective To investigate the effect of selenium supplementation on the selenium status and selenoenzyme, especially the activity and mRNA expression of type 1 deiodinase (D1) in mice with excessive iodine (EI) intake and to explore the mechanism of selenium intervention on iodine-induced abnormities. Methods Weanling female BALB/c mice were given tap water or 3 mg/L of iodine or supplemented with 0.5 mg/L or 1.0 mg/L of selenium in the presence of excessive iodine for 5 months. Selenium status, thyroid hormone level, hepatic and renal D 1 activity and mRNA expression were examined. Results Excessive iodine intake significantly decreased the selenium concentration in urine and liver, and the activity of glutathione peroxidase (GSH-Px) in liver. Meanwhile, serum total T4 (TT4) increased while serum total T3 (TT3) decreased. Hepatic D1 enzyme activity and mRNA expression were reduced by 33% and 86%, respectively. Renal D1 enzyme activity and mRNA were reduced by 30% and 55%, respectively. Selenium supplementation obviously increased selenium concentration, activity of GSH-Px and D1 as well as mRNA expression of D1. However, increasing the supplementation of Se from 0.5 to 1.0 mg/L did not further increase selenoenzyme activity and expression. Conclusion Relative selenium deficiency caused by excessive iodine plays an essential role in the mechanism of iodine-induced abnormalities. An appropriate dose of selenium supplementation exercises a beneficial intervention. 展开更多
关键词 excessive iodine SELENIUM Glutathione peroxidase Type 1 deiodinase
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