Percussion drilling is a promising approach for hot dry rock(HDR)fragmentation.However,understanding of HDR fragmentation mechanism under multi-dimensional percussion remains limited and hinders the corresponding dril...Percussion drilling is a promising approach for hot dry rock(HDR)fragmentation.However,understanding of HDR fragmentation mechanism under multi-dimensional percussion remains limited and hinders the corresponding drilling performance.Herein,an innovative true triaxial multi-dimensional percussion device was developed for the study of HDR fragmentation mechanism under in-situ temperature and stress conditions.Multi-dimensional percussion,involving both axial and torsional components,was applied to drilling in granite and carbonatite rocks sampled from the typical HDR target areas.Multiscale visualization techniques and a whale optimization-variational mode decomposition algorithm were employed to investigate the rock failure patterns and drilling energy characteristics.Results indicated that multi-dimensional percussion enhances brittle-ductile mixed failure in granite,characterized by transgranular,intergranular,and combined fracture patterns that promote rock cracking.In contrast,carbonatite drillhole displays enhanced brittle fragmentation and tortuous failure surface dominated by transgranular fracture pattern.Frequency-domain characteristics of penetration force signals for multidimensional percussion,especially the significant dominant frequency,amplitude,and high-frequency dissipation,indicate an increase in net energy for drilling into HDR and intensified rock fragmentation.Further,the effect of impact frequency on rock fragmentation performance was emphasized to maximize drilling efficiency.The optimal regulation schemes between axial and torsional impact frequencies are identified as 15 Hz+15 Hz for granite and 30 Hz+15 Hz for carbonatite.The reliability of the optimization approach was validated through a field test that employed a novel impactor in the geothermal well Fushen-1.展开更多
本文采用电熔炉冶炼低品位DRI,开展百公斤级扩大化试验,探索低品位DRI电熔炉冶炼特性,包括渣铁分离效果、铁水渗碳效果、铁收得率等,并利用设计软件计算吨铁电耗、煤耗等指标。试验结果表明,DRI球由于具有团疏松多孔的结构,在熔炼过程...本文采用电熔炉冶炼低品位DRI,开展百公斤级扩大化试验,探索低品位DRI电熔炉冶炼特性,包括渣铁分离效果、铁水渗碳效果、铁收得率等,并利用设计软件计算吨铁电耗、煤耗等指标。试验结果表明,DRI球由于具有团疏松多孔的结构,在熔炼过程中始终漂浮在熔池上方;在二次电压120 V下,电极始终为浸没式操作,不能实现刷弧或明弧操作。通过从顶部加入无烟煤和DRI的混合物料可以实现良好的铁还原和铁水渗碳效果,铁水含碳量平均值为3.09%。在低碱度渣型和高渣率下,所得渣Fe O含量平均值为1.47%,铁收得率平均值高达98.84%。低品位DRI热态入炉生产液体热金属所需的理论吨铁电耗为511 k W·h/t,而冷态入炉的理论吨铁电耗为770 k W·h/t,热态DRI直接入炉冶炼可以节能约50%。展开更多
Background Feeding spray dried plasma(SDP)to weanling pigs improves growth,but there is a lack of research on how SDP impacts oxidative stress and inflammatory response in lactating sows,and performance of their pigle...Background Feeding spray dried plasma(SDP)to weanling pigs improves growth,but there is a lack of research on how SDP impacts oxidative stress and inflammatory response in lactating sows,and performance of their piglets after weaning.Therefore,an experiment was conducted to test the hypothesis that sows fed a diet with SDP in late gestation and lactation have improved reproductive performance and reduced inflammation compared with sows fed no SDP.The second hypothesis was that pigs weaned from sows fed 0.5%SDP in lactation have reduced diarrhea incidence and improved growth performance during the initial 14 d of the nursery period regardless of dietary SDP.Results The percent of low vitality or starved pigs during lactation was less(P<0.05)from sows fed 0.5%dietary SDP compared with sows fed the diet without SDP.Dietary SDP did not influence oxidative stress markers in the plasma of sows,but serum cytokines increased(P<0.05)in sows fed the diet with 0.5%SDP compared with sows fed the diet without SDP.Pigs weaned from young sows fed no SDP or from mature sows fed 0 or 0.5%SDP had a greater gain to feed ratio when fed a phase 1 diet containing 6%SDP compared with pigs fed a diet without SDP,but the gain to feed ratio of pigs weaned from young sows fed 0.5%dietary SDP was not affected by dietary SDP in phase 1(interaction,P<0.05).Regardless of sow treatment,pigs fed a phase 1 diet with 6%SDP had greater(P<0.05)growth performance than pigs fed a phase 1 diet without SDP,and pigs fed the phase 1 diet with 6%SDP had reduced(P<0.05)diarrhea incidence in phase 1.Conclusions Feeding 0.5%dietary SDP to sows may reduce the number of mummified pigs and increase pig vitality during lactation,but adding 0.5%SDP to sow diets during lactation did not improve post-weaning performance of pigs fed a starter diet with 6%SDP.展开更多
AIM:To investigate the association between active corneal epithelial dendritic cells(CEDCs)and ocular pain in patients with dry eye disease(DED).METHODS:This cross-sectional study enrolled 67 DED patients,who were div...AIM:To investigate the association between active corneal epithelial dendritic cells(CEDCs)and ocular pain in patients with dry eye disease(DED).METHODS:This cross-sectional study enrolled 67 DED patients,who were divided into two groups based on numerical rating scale(NRS)scores:the mild pain group(n=44)and the moderate-to-severe pain group(n=23).In vivo confocal microscopy(IVCM)was used to image the subbasal layer of the central cornea.Corneal nerve characteristics were analyzed using ACCMetrics software,while CEDCs were quantified manually with Image J software.Regression and correlation analyses were performed to assess the impact of active CEDCs on ocular pain.Additionally,the Luminex method was employed to compare the concentrations of inflammation-related cytokines in tears between patients with≥2 CEDCs and those with<2 CEDCs.Differences in cytokine levels between the two groups were analyzed using Student’s t-test.RESULTS:The study included 44 eyes of 44 patients with mild ocular pain(12 males and 32 females)and 23 eyes of 23 patients with moderate-to-severe ocular pain(3 males and 20 females).The mean age was 36.2±13.5y in the mild pain group and 39.7±12.4y in the moderate to severe pain group.There were no significant differences in age or sex between the two groups(P=0.30;P=0.19).Multivariable regression analysis showed that older age[odds ratio(OR)=1.05,95%confidence interval(CI)1.00–1.11]and a higher number of CEDCs(OR=1.80,95%CI 1.17–2.76)were associated with ocular pain.Patients with≥2 CEDCs had significantly higher tear concentrations of interleukin(IL)-6(P<0.05),IL-8(P<0.05),and tumor necrosis factor(TNF)-α(P<0.05)compared to those with<2 active CEDCs.CONCLUSION:The findings suggest that infiltrating CEDCs in the corneal subbasal layer are a potential risk factor for ocular pain in DED.展开更多
基金supported by the Major Program of National Natural Science Foundation of China(No.52192624)the Innovative Research Group Project of National Natural Science Foundation of China(No.52421002)+3 种基金Major Science and Technology Project of Yunnan Province(No.202302AF080001)NSFC Key International(Regional)Cooperative Research Projects(No.52020105001)General Program of National Natural Science Foundation of China(Nos.52204019 and 52274016)the Foundation of State Key Laboratory of Petroleum Resources and Prospecting(No.PRE/DX-2402)。
文摘Percussion drilling is a promising approach for hot dry rock(HDR)fragmentation.However,understanding of HDR fragmentation mechanism under multi-dimensional percussion remains limited and hinders the corresponding drilling performance.Herein,an innovative true triaxial multi-dimensional percussion device was developed for the study of HDR fragmentation mechanism under in-situ temperature and stress conditions.Multi-dimensional percussion,involving both axial and torsional components,was applied to drilling in granite and carbonatite rocks sampled from the typical HDR target areas.Multiscale visualization techniques and a whale optimization-variational mode decomposition algorithm were employed to investigate the rock failure patterns and drilling energy characteristics.Results indicated that multi-dimensional percussion enhances brittle-ductile mixed failure in granite,characterized by transgranular,intergranular,and combined fracture patterns that promote rock cracking.In contrast,carbonatite drillhole displays enhanced brittle fragmentation and tortuous failure surface dominated by transgranular fracture pattern.Frequency-domain characteristics of penetration force signals for multidimensional percussion,especially the significant dominant frequency,amplitude,and high-frequency dissipation,indicate an increase in net energy for drilling into HDR and intensified rock fragmentation.Further,the effect of impact frequency on rock fragmentation performance was emphasized to maximize drilling efficiency.The optimal regulation schemes between axial and torsional impact frequencies are identified as 15 Hz+15 Hz for granite and 30 Hz+15 Hz for carbonatite.The reliability of the optimization approach was validated through a field test that employed a novel impactor in the geothermal well Fushen-1.
文摘本文采用电熔炉冶炼低品位DRI,开展百公斤级扩大化试验,探索低品位DRI电熔炉冶炼特性,包括渣铁分离效果、铁水渗碳效果、铁收得率等,并利用设计软件计算吨铁电耗、煤耗等指标。试验结果表明,DRI球由于具有团疏松多孔的结构,在熔炼过程中始终漂浮在熔池上方;在二次电压120 V下,电极始终为浸没式操作,不能实现刷弧或明弧操作。通过从顶部加入无烟煤和DRI的混合物料可以实现良好的铁还原和铁水渗碳效果,铁水含碳量平均值为3.09%。在低碱度渣型和高渣率下,所得渣Fe O含量平均值为1.47%,铁收得率平均值高达98.84%。低品位DRI热态入炉生产液体热金属所需的理论吨铁电耗为511 k W·h/t,而冷态入炉的理论吨铁电耗为770 k W·h/t,热态DRI直接入炉冶炼可以节能约50%。
基金support from APC LLC,Ankeny,IA,USA,is greatly appreciated.
文摘Background Feeding spray dried plasma(SDP)to weanling pigs improves growth,but there is a lack of research on how SDP impacts oxidative stress and inflammatory response in lactating sows,and performance of their piglets after weaning.Therefore,an experiment was conducted to test the hypothesis that sows fed a diet with SDP in late gestation and lactation have improved reproductive performance and reduced inflammation compared with sows fed no SDP.The second hypothesis was that pigs weaned from sows fed 0.5%SDP in lactation have reduced diarrhea incidence and improved growth performance during the initial 14 d of the nursery period regardless of dietary SDP.Results The percent of low vitality or starved pigs during lactation was less(P<0.05)from sows fed 0.5%dietary SDP compared with sows fed the diet without SDP.Dietary SDP did not influence oxidative stress markers in the plasma of sows,but serum cytokines increased(P<0.05)in sows fed the diet with 0.5%SDP compared with sows fed the diet without SDP.Pigs weaned from young sows fed no SDP or from mature sows fed 0 or 0.5%SDP had a greater gain to feed ratio when fed a phase 1 diet containing 6%SDP compared with pigs fed a diet without SDP,but the gain to feed ratio of pigs weaned from young sows fed 0.5%dietary SDP was not affected by dietary SDP in phase 1(interaction,P<0.05).Regardless of sow treatment,pigs fed a phase 1 diet with 6%SDP had greater(P<0.05)growth performance than pigs fed a phase 1 diet without SDP,and pigs fed the phase 1 diet with 6%SDP had reduced(P<0.05)diarrhea incidence in phase 1.Conclusions Feeding 0.5%dietary SDP to sows may reduce the number of mummified pigs and increase pig vitality during lactation,but adding 0.5%SDP to sow diets during lactation did not improve post-weaning performance of pigs fed a starter diet with 6%SDP.
基金Supported by the National Natural Science Foundation of China(No.82171022No.81974128).
文摘AIM:To investigate the association between active corneal epithelial dendritic cells(CEDCs)and ocular pain in patients with dry eye disease(DED).METHODS:This cross-sectional study enrolled 67 DED patients,who were divided into two groups based on numerical rating scale(NRS)scores:the mild pain group(n=44)and the moderate-to-severe pain group(n=23).In vivo confocal microscopy(IVCM)was used to image the subbasal layer of the central cornea.Corneal nerve characteristics were analyzed using ACCMetrics software,while CEDCs were quantified manually with Image J software.Regression and correlation analyses were performed to assess the impact of active CEDCs on ocular pain.Additionally,the Luminex method was employed to compare the concentrations of inflammation-related cytokines in tears between patients with≥2 CEDCs and those with<2 CEDCs.Differences in cytokine levels between the two groups were analyzed using Student’s t-test.RESULTS:The study included 44 eyes of 44 patients with mild ocular pain(12 males and 32 females)and 23 eyes of 23 patients with moderate-to-severe ocular pain(3 males and 20 females).The mean age was 36.2±13.5y in the mild pain group and 39.7±12.4y in the moderate to severe pain group.There were no significant differences in age or sex between the two groups(P=0.30;P=0.19).Multivariable regression analysis showed that older age[odds ratio(OR)=1.05,95%confidence interval(CI)1.00–1.11]and a higher number of CEDCs(OR=1.80,95%CI 1.17–2.76)were associated with ocular pain.Patients with≥2 CEDCs had significantly higher tear concentrations of interleukin(IL)-6(P<0.05),IL-8(P<0.05),and tumor necrosis factor(TNF)-α(P<0.05)compared to those with<2 active CEDCs.CONCLUSION:The findings suggest that infiltrating CEDCs in the corneal subbasal layer are a potential risk factor for ocular pain in DED.