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An autotrophic nitrogen removal process:Short-cut nitrification combined with ANAMMOX for treating diluted effluent from an UASB reactor fed by landfill leachate 被引量:26
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作者 Jie Liu Jian'e Zuo +3 位作者 Tang Yang Shuquan Zhu Sulin Kuang Kaijun Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期777-783,共7页
A combined process consisting of a short-cut nitrification (SN) reactor and an anaerobic ammonium oxidation upflow anaerobic sludge bed (ANAMMOX) reactor was developed to treat the diluted effluent from an upflow ... A combined process consisting of a short-cut nitrification (SN) reactor and an anaerobic ammonium oxidation upflow anaerobic sludge bed (ANAMMOX) reactor was developed to treat the diluted effluent from an upflow anaerobic sludge bed (UASB) reactor treating high ammonium municipal landfill leachate.The SN process was performed in an aerated upflow sludge bed (AUSB) reactor (working volume 3.05 L),treating about 50% of the diluted raw wastewater.The ammonium removal efficiency and the ratio of NO 2 N to NOx-N in the effluent were both higher than 80%,at a maximum nitrogen loading rate of 1.47 kg/(m 3 ·day).The ANAMMOX process was performed in an UASB reactor (working volume 8.5 L),using the mix of SN reactor effluent and diluted raw wastewater at a ratio of 1:1.The ammonium and nitrite removal efficiency reached over 93% and 95%,respectively,after 70-day continuous operation,at a maximum total nitrogen loading rate of 0.91 kg/(m 3 ·day),suggesting a successful operation of the combined process.The average nitrogen loading rate of the combined system was 0.56 kg/(m 3 ·day),with an average total inorganic nitrogen removal efficiency 87%.The nitrogen in the effluent was mostly nitrate.The results provided important evidence for the possibility of applying SN-ANAMMOX after UASB reactor to treat municipal landfill leachate. 展开更多
关键词 landfill leachate short-cut nitrification anaerobic ammonia oxidation autotrophic nitrogen removal
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Identification and Metabolic Mechanism of Non-fermentative Short-cut Denitrifying Phosphorus-removing Bacteria 被引量:12
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作者 刘晖 孙彦富 +5 位作者 贾晓珊 李军 周康群 屈向东 陶雪琴 陈瑜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第3期332-340,共9页
To investigate the characteristics and metabolic mechanism of short-cut denitrifying phospho- rus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an elec... To investigate the characteristics and metabolic mechanism of short-cut denitrifying phospho- rus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand (COD), phosphate, nitrite, poly-fl-hydroxybutyrate (PHB), and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release (96.2%) under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation (91.3%) and a little for glycogen synthesis (8.7%). This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms (PAOs). It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring AP/APHB and ANO2 -N/APHB is more necessary than monitoring AP/ACOD, ANO2 -N/ACOD, or AP / ANO2 -N. 展开更多
关键词 short-cut denitrifying phosphorus removing bacteria Paracoccus denitrificans non-fermentative bac- teria metabolic mechanism poly-fl-hydroxybutyrate
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Nitrogen removal from coal gasification wastewater by activated carbon technologies combined with short-cut nitrogen removal process 被引量:4
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作者 Qian Zhao Hongjun Han +3 位作者 Baolin Hou Haifeng Zhuang Shengyong Jia Fang Fang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第11期2231-2239,共9页
A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anae... A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand (COD) degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater (CGW). 展开更多
关键词 Coal gasification wastewater short-cut nitrogen removal Granular activated carbon PCR-DGGE Denitrification enhancement
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Effects of Short-cut Flowering Branches on Harvest Time,Yield and Quality of Guire No.82 Mango
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作者 Shudan WEI Qianfu CHEN +6 位作者 Yong ZHONG Qiang JIANG Jie HUANG Yerong WANG Huili HUANG Jinying YANG Yuanxin CAO 《Asian Agricultural Research》 2022年第7期51-54,57,共5页
[Objectives]To further study the technology of short-cut flowering branches for Guire No.82 Mango,adjust its harvest time,increase yield and improve fruit quality,and increase the economic benefits of mango production... [Objectives]To further study the technology of short-cut flowering branches for Guire No.82 Mango,adjust its harvest time,increase yield and improve fruit quality,and increase the economic benefits of mango production.[Methods]The experiment of short-cut flowering branches was carried out for Guire No.82 Mango.[Results]At the initial flowering stage and full flowering stage of the primary inflorescence,with short-cut flowering branches and corresponding cultivation techniques,Guire No.82 Mango was easy to extract regenerated inflorescences.Compared with the control group,the flowering period of the regenerated inflorescences was delayed by 30-35 d and 40-50 d,respectively;the harvest time was delayed by 30 and 40 d,respectively;the yield significantly increased by 1.63 times and 2.25 times,respectively;compared with the control group,the number of fruits with embryo increased significantly,which were 1.39 and 2.25 times of the control,respectively;there was no significant difference in the fruit quality at the harvest time.[Conclusions]Short-cut flowering branches at the initial flowering stage and full flowering stage of the primary inflorescence is an effective measure to delay the marketing time of Guire No.82 Mango. 展开更多
关键词 short-cut flowering branches Guire No.82 Mango Harvest time YIELD Fruit quality
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Effects of Hydroxylamine on Nitrite and Elemental Sulfur Accumulation During Short-cut Sulfur Autotrophic Denitrification
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作者 Gong Xihui Li Shiwen +3 位作者 Wang Wenna Wang Chentao Wang Shengyuan Liu Chunshuang 《China Petroleum Processing & Petrochemical Technology》 CSCD 2024年第4期9-17,共9页
This study investigates the simultaneous accumulation of S^(0) and NO_(2)^(-)during short-cut sulfur autotrophic denitrification(SSADN)in response to 0-35 mg/L hydroxylamine(NH_(2)OH)addition.At a dosage of 15 mg/L NH... This study investigates the simultaneous accumulation of S^(0) and NO_(2)^(-)during short-cut sulfur autotrophic denitrification(SSADN)in response to 0-35 mg/L hydroxylamine(NH_(2)OH)addition.At a dosage of 15 mg/L NH_(2)OH,the accumulation of NO_(2)^(-)-N peaked at 32.49±1.33 mg/L,which is 1.65 times higher than that of the control.The addition of NH_(2)OH facilitates the retention of S^(0) in the system.Enzyme assays indicated significant discrepancies in the enhanced NO_(2)^(-)-N reductase(NAR)and NO_(2)^(-)-N reductase(NIR)activities induced by NH_(2)OH are responsible for the excellent NO_(2)^(-)-N production.These results are supported by the corresponding NO_(3)^(-)-N reduction genes(napA,narG)and NO_(2)^(-)-N reduction genes(nirS,nirK).In addition,the abundance of sulfur oxidation genes(soxB)decreases with increasing NH_(2)OH dosage,inhibiting further oxidation of S^(0) to SO_(4)^(2-).The accumulation of NO_(2)^(-)-N and S^(0) increases from 45.8% and 36.8% to 70.04% and 52.52%,respectively,with the addition of 2 mg/L NH_(2)OH in the continuous-flow up-flow anaerobic sludge blanket(UASB)reactor. 展开更多
关键词 NH_(2)OH short-cut sulfur autotrophic denitrification S^(0) accumulation NO_(2)^(-) accumulation
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Reconsidering the Future of Seawater Desalination in China:Proposal of Constructing Short-cut Water Cycle in Coastal Areas
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作者 Hui Gong Shuyan Zhou +1 位作者 Guodong Xu Kaijun Wang 《Water & Ecology》 2025年第2期127-136,126,共11页
Water scarcity is a pressing issue that threatens sustainable development worldwide,especially in regions like China,where natural freshwater resources are increasingly strained by rapid urbanization,climate change,an... Water scarcity is a pressing issue that threatens sustainable development worldwide,especially in regions like China,where natural freshwater resources are increasingly strained by rapid urbanization,climate change,and ecological demands.While seawater desalination offers a strategic freshwater augmentation pathway,its large-scale application remains constrained by challenges including public perception gaps(eg,how to understand water scarcity),technoeconomic barriers,and developmental paradigm controversies.Through comprehensive analysis grounded in firstprinciples thinking,this research re-evaluates seawater desalination as a transformative solution to water scarcity,incorporating assessments compared to conventional water supply systems.This study proposes a novel“100-Kilometer Coastal Desalination for Short-cut water cycle(100K-CDS)”strategy for China,leveraging its extensive coastline to industrialize water production.Key findings reveal that modern reverse osmosis technology has achieved significant cost reductions through technological advancement and economies of scale.The integration of renewable energy sources could reduce desalination’s carbon footprint by 57.5%~98.3%compared to conventional systems.Implementing coastal desalination strategies will not only effectively alleviate regional water demands of coast areas,which account for 40%of the nation’s population and over 50%of its GDP.This research contributes a paradigm-shifting framework for treating desalinated freshwater as a manufacturable resource rather than a finite natural commodity,offering promotable insights for water-scarce regions worldwide and advancing global water sustainability through industrial-scale desalination. 展开更多
关键词 water scarcity seawater desalination short-cut water cycle desalination technology water resource management
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Sludge fermentation liquid addition attained advanced nitrogen removal in low C/N ratio municipal wastewater through short-cut nitrification-denitrification and partial anammox 被引量:11
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作者 Shengjie Qiu Jinjin Liu +2 位作者 Liang Zhang Qiong Zhang Yongzhen Peng 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2021年第2期107-116,共10页
Biological nitrogen removal of wastewater with low COD/N ratio could be enhanced by the addition of wasted sludge fermentation liquid(SFL),but the performance is usually limited by the introducing ammonium.In this stu... Biological nitrogen removal of wastewater with low COD/N ratio could be enhanced by the addition of wasted sludge fermentation liquid(SFL),but the performance is usually limited by the introducing ammonium.In this study,the process of using SFL was successfully improved by involving anammox process.Real municipal wastewater with a low C/N ratio of 2.8–3.4 was treated in a sequencing batch reactor(SBR).The SBR was operated under anaerobic-aerobic-anoxic(AOA)mode and excess SFL was added into the anoxic phase.Stable short-cut nitrification was achieved after 46d and then anammox sludge was inoculated.In the stable period,effluent total inorganic nitrogen(TIN)was less than 4.3 mg/L with removal efficiency of 92.3%.Further analysis suggests that anammox bacteria,mainly affiliated with Candidatus_Kuenenia,successfully reduced the external ammonia from the SFL and contributed approximately 28%–43%to TIN removal.Overall,this study suggests anammox could be combined with SFL addition,resulting in a stable enhanced nitrogen biological removal. 展开更多
关键词 Sludge fermentation liquid Municipal wastewater Advanced nitrogen removal short-cut nitrification Partial anammox
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Validity of Amontons's law for run-in short-cut aramid fiber reinforced elastomers:The effect of epoxy coated fibers 被引量:1
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作者 M.KHAFIDH D.J.SCHIPPER +3 位作者 M.A.MASEN N.VLEUGELS W.K.DIERKES J.W.M.NOORDERMEER 《Friction》 SCIE CSCD 2020年第3期613-625,共13页
Friction between two contacting surfaces is studied extensively.One of the k n o w n friction theories is Amontons,law which states that the friction force is proportional to the normal force.However,Amontons7 law has... Friction between two contacting surfaces is studied extensively.One of the k n o w n friction theories is Amontons,law which states that the friction force is proportional to the normal force.However,Amontons7 law has been found to be invalid for elastomers.In the present study,the validity of Amontons7 law for short-cut aramid fiber reinforced elastomers is studied.Two types of fillers are used to reinforce the elastomers,namely highly dispersible silica and short-cut aramid fibers.Short-cut aramid fibers with two different surface treatments are used,namely non-reactive fibers with standard oily finish(SF-fibers)and fibers treated with an epoxy coating(EF-fibers).A pin-on-disc tribometer is used to investigate the frictional behavior of the composites in sliding contact with a granite counter surface.The results show that,after the run-in phase,Amontons,law is valid for those composites that are reinforced by short-cut aramid fibers(without reinforcing filler,i.e.,silica)if the contact pressure is below a threshold value.However,once the contact pressure exceeds this threshold value,Amontons'law will be invalid.The threshold contact pressure of the composites containing EF-fibers is higher than of the composites containing SF-fibers.The composites that are reinforced by silica and short-cut aramid fibers do not follow Amontons7 law. 展开更多
关键词 Amontons's law ELASTOMER epoxy coated fiber short-cut aramid fiber
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Production of N2O in two biologic nitrogen removal processes: a comparison between conventional and short-cut Nitrogen removal processes 被引量:2
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作者 Youkui GONG Yongzhen PENG +1 位作者 Shuying WANG Sai WANG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2014年第4期589-597,共9页
The N2O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors (SBRs). Results showed that N2O emission happened in th... The N2O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors (SBRs). Results showed that N2O emission happened in the aerobic phase rather than in the anoxic phase. During the aerobic phase, the nitrogen conversion to N2O gas was 27.7% and 36.8% of NH+-N loss for conventional biologic N-removal process and short-cut biologic N-removal process. The dissolved N2O was reduced to N2 in the anoxic denitrification phase. The N2O production rate increased with the increasing of nitrite concentration and ceased when NH+-N oxidation was terminated. Higher nitrite accumulation resulted in higher NEO emission in the short-cut nitrogen removal process. Pulse-wise addition of 20 mg NO2 -N. L- 1 gave rise to 3-fold of N2O emission in the conventional N-removal process, while little change happened with 20 mg NOS-N L-1 was added to SBR1. 展开更多
关键词 conventional N-removal process N2O short- cut N-removal process nitrite accumulation ammonia-oxidizing bacteria (AOB) denitrification
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基于简化相平衡关联式的高效简捷精馏塔模型
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作者 王宗廷 王丽丽 +3 位作者 孙晓岩 夏力 陶少辉 项曙光 《化工学报》 北大核心 2025年第3期1133-1142,共10页
化工单元的准确快速模拟是化工数字孪生成功实施的关键之一。精馏塔作为最复杂和应用最广泛的化工单元之一,其高效准确求解对于实现化工装置数字孪生具有重要意义。传统精馏塔模型则由于规模较大和热力学性质计算耗时等原因,形成了制约... 化工单元的准确快速模拟是化工数字孪生成功实施的关键之一。精馏塔作为最复杂和应用最广泛的化工单元之一,其高效准确求解对于实现化工装置数字孪生具有重要意义。传统精馏塔模型则由于规模较大和热力学性质计算耗时等原因,形成了制约其数字孪生的瓶颈。为此,在简捷精馏塔模型基础上,引入了组分相平衡常数与温度间关联式,以简化相平衡计算,并基于此提出了烃类精馏塔的高效简捷精馏塔模型。最后,通过实际工业中的精馏塔进行验证,结果表明所提出的高效简捷精馏塔模型能有效减少计算耗时,为精馏塔的数字孪生建模奠定了基础。 展开更多
关键词 模型简化 过程系统 计算机模拟 数字孪生 简捷精馏塔模型
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高温胁迫对茶树短穗扦插繁育的影响 被引量:1
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作者 王鲲鹏 张明洁 +5 位作者 宋大鹏 周超 厉辉 王立岩 许永玉 丁仕波 《西北农林科技大学学报(自然科学版)》 北大核心 2025年第10期42-51,共10页
【目的】明确高温胁迫对茶树短穗扦插繁育的影响,为山东茶区茶树短穗扦插繁育提供参考。【方法】以“中茶108”为短穗扦插材料,分别在25,30和35℃下培养,于培养1,3,5,7和9 d时,观测不同温度处理下插穗形态表征的变化,统计插穗的损伤率... 【目的】明确高温胁迫对茶树短穗扦插繁育的影响,为山东茶区茶树短穗扦插繁育提供参考。【方法】以“中茶108”为短穗扦插材料,分别在25,30和35℃下培养,于培养1,3,5,7和9 d时,观测不同温度处理下插穗形态表征的变化,统计插穗的损伤率和死亡率,并分析对插穗叶片光合色素含量、叶绿素荧光参数、O^(-)_(2)产生速率、抗氧化酶活性和脯氨酸含量的影响;在培养3和7 d时观察插穗叶片叶绿体超微结构变化。【结果】25℃处理茶树插穗几乎未受损伤,死亡率为0;30℃处理7 d插穗开始受损死亡,9 d时死亡率为35.7%;35℃处理5 d插穗开始受损,7 d开始死亡,9 d时死亡率为64.3%。25℃处理茶树插穗叶片叶绿体形态饱满规则;30和35℃处理随着时间延长,叶绿体结构受到不同程度损伤。茶树插穗叶片叶绿素a、叶绿素b、类胡萝卜素和总叶绿素含量在25℃处理期间波动较小,在30和35℃处理下随高温胁迫时间延长逐渐降低。25℃下茶树插穗叶片叶绿素荧光最大光化学效率(F_(v)/F_(m))、单位活性反应中心吸收的能量(ABS/RC)、单位活性反应中心捕获的用于还原初级醌受体(QA)的能量(TR 0/RC)、单位活性反应中心捕获的用于传递的电子能量(ET 0/RC)、单位活性反应中心耗散的能量(DI 0/RC)以及基于ABS的PSⅡ功能活性指数(PI ABS)在处理期间基本保持稳定,30和35℃处理插穗叶片的F_(v)/F_(m)和PI ABS随处理时间延长而降低,ABS/RC、TR 0/RC和DI 0/RC随处理时间延长明显增加,ET 0/RC在处理后期开始低于25℃处理。3个温度处理下,茶树插穗叶片O^(-)_(2)产生速率均随着处理时间的延长不断上升。25℃处理茶树插穗叶片的POD活性在处理期间呈上升趋势,30和35℃处理均呈先下降后上升的趋势;3个温度处理插穗叶片的APX和CAT活性在处理期间均呈先上升后下降的趋势。3个温度处理插穗叶片的脯氨酸含量均随处理时间延长而上升,其中35℃处理脯氨酸含量增幅最大。【结论】高温胁迫会对茶树插穗扦插成活率和生理特性造成严重影响,在茶树短穗扦插繁育过程中,育苗棚内温度应避免超过30℃,高于30℃时需及时通风降温。 展开更多
关键词 茶树 短穗扦插 高温胁迫 生理特性 死亡率
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修剪方式对薄壳山核桃生长发育和果实品质的影响
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作者 周智 杜洋文 +3 位作者 程军勇 雷学志 丁志刚 肖新意 《经济林研究》 北大核心 2025年第1期255-263,290,共10页
【目的】为促进薄壳山核桃早实丰产提供依据。【方法】以9年生薄壳山核桃嫁接植株为研究对象,采用不同的枝条皮部处理、短截、拉枝等措施进行修剪,调查新枝生长情况,测定结果枝顶芽的可溶性糖、淀粉、蛋白质、全氮及脱落酸含量,测定果... 【目的】为促进薄壳山核桃早实丰产提供依据。【方法】以9年生薄壳山核桃嫁接植株为研究对象,采用不同的枝条皮部处理、短截、拉枝等措施进行修剪,调查新枝生长情况,测定结果枝顶芽的可溶性糖、淀粉、蛋白质、全氮及脱落酸含量,测定果实的可溶性糖含量、淀粉含量、蛋白质含量、果实含油率、饱和脂肪酸和不饱和脂肪酸含量等。【结果】与对照相比,扭皮、环割和削皮3种皮部处理的总成枝率、新成枝率、新结果枝率、总结果枝率和新结果枝占比均显著提高,各处理的结果枝顶芽碳氮比以及果实中可溶性糖(削皮处理除外)、淀粉、蛋白质、不饱和脂肪酸含量均显著高于对照,以扭皮处理的效果最佳,削皮和环剥处理次之,总结果枝数量增加27.27%~47.98%,新结果枝数量增加12.50%~28.65%,不饱和脂肪酸含量均达到91%以上。不同短截处理后,新成枝数量、成枝率和结果枝顶芽的碳氮比均显著高于对照,短截2/3和短截1/2处理的新成枝率最高达79.24%,比对照高48.61个百分点,短截1/2和剪顶芽处理的果实蛋白质含量显著高于对照,前者比对照高出35.39%。不同拉枝角度处理的成枝率显著高于对照,各处理的结果枝顶芽的可溶性糖、淀粉、蛋白质、全氮含量以及碳氮比均显著提高,拉枝60°~90°和拉枝90°~120°处理的新成枝率达53.90%~60.19%,比对照高45.47~51.76个百分点,3种拉枝处理的可溶性糖、淀粉、蛋白质和全氮含量分别比对照高92.60%~137.04%、31.59%~40.59%、15.74%~37.05%和15.40%~37.17%。【结论】扭皮、剪顶芽、短截1/3、拉枝60°~90°和拉枝90°~120°处理能显著促进新枝生长、促进结果枝形成和提高果实品质。 展开更多
关键词 薄壳山核桃 生长发育 短截 环剥 拉枝
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小断面隧洞长短直眼组合掏槽爆破技术研究 被引量:1
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作者 王磊 高宇璠 +4 位作者 傅洪贤 穆垣宏 刘研 左春元 李庆京 《爆破》 北大核心 2025年第2期97-104,共8页
为了提高小断面隧洞掘进速度,克服斜眼掏槽和直眼掏槽的不足,根据岩石爆破理论、应力波破岩理论和殉爆理论,对井巷无空孔渐进等抵抗线平行掏槽方法进行完善改进,提出了一种长短直眼组合掏槽方式,对该方法的参数设计、槽腔形成过程进行... 为了提高小断面隧洞掘进速度,克服斜眼掏槽和直眼掏槽的不足,根据岩石爆破理论、应力波破岩理论和殉爆理论,对井巷无空孔渐进等抵抗线平行掏槽方法进行完善改进,提出了一种长短直眼组合掏槽方式,对该方法的参数设计、槽腔形成过程进行了详细的分析介绍。结合现场试验,通过使用不同雷管和掏槽孔布置方式,从爆破进尺、炸药单耗和超欠挖量等几个角度分析了不同掏槽方式爆破效果的优劣。结果表明:长短直眼组合掏槽不受断面面积限制,可自行设计孔深,并采用合理的延时间隔,以实现分层分次爆破;长直眼与短直眼互相配合,增强了自由面在掏槽过程中的作用,减少了深孔最小抵抗线的距离;长短直眼组合掏槽的槽腔形状为规则的长方体,炮孔利用率由78.5%增加到89.3%。现场试验表明:在小断面隧洞爆破掘进中,长短直眼组合掏槽方式相较于传统的斜眼掏槽,爆破进尺由1.6~2.2 m可提升2.2~2.5 m;超挖量受到周边孔内移量和掏槽形式的综合作用,在内移10 cm以内的情况下,长短直眼组合掏槽爆破可额外减少超挖20%~30%。该方法可有效控制成本,提高工效,具有良好的爆破效果和技术经济效益。 展开更多
关键词 隧洞爆破工程 现场试验 小断面 长短直眼 掏槽爆破
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短切纤维对Al/PTFE-RDX组合装药力学行为和爆炸性能的影响
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作者 朱守军 程扬帆 +2 位作者 张启威 朱容康 陈子涵 《火炸药学报》 北大核心 2025年第12期1143-1153,I0003,共12页
为了探究短切纤维对组合装药力学性能和爆炸特性的影响规律,制备了一种含有短切纤维的增强型Al/PTFE活性材料环,并与RDX药柱形成组合装药;利用万能材料试验机和分离式霍普金森杆(SHPB)系统研究了含不同种类短切纤维的Al/PTFE活性材料环... 为了探究短切纤维对组合装药力学性能和爆炸特性的影响规律,制备了一种含有短切纤维的增强型Al/PTFE活性材料环,并与RDX药柱形成组合装药;利用万能材料试验机和分离式霍普金森杆(SHPB)系统研究了含不同种类短切纤维的Al/PTFE活性材料环的力学行为;采用自由场爆炸测试系统、球形爆炸容器测试系统和比色测温技术,深入研究了不同短切纤维对组合装药准静态压力、冲击波参数和爆炸火球特征参数的影响。结果表明,短切纤维可以显著地提高Al/PTFE活性材料环的力学性能,其中含短切钛纤维Al/PTFE活性材料环的抗压强度为6.12 MPa,抗冲击强度为15.433 MPa,较不含纤维的Al/PTFE活性材料环提高了134.8%和93.1%,其表现出最优异的抗压性能和抗冲击能力;含短切钛纤维组合装药的冲击波峰值压力为37.68 kPa、正相作用时间为695.34μs、正冲量为12.34 Pa·s、准静态压力为58.21 kPa、火球平均最大温度为2734 K,火球持续时间为1375.64μs,较未添加短切纤维组合装药分别提升了19.1%、5.8%、25.0%、70.1%、3.9%和51.6%,短切钛纤维对组合装药的爆炸性能提升最为显著;表明短切钛纤维在改善组合装药力学性能和爆炸威力方面具有很好的应用前景。 展开更多
关键词 爆炸力学 短切纤维 活性材料 组合装药 纤维增强 后燃反应 PTFE 金属-氟聚物
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以聚硅氮烷为前驱体制备碳纤维网胎增强碳化硅陶瓷基复合材料
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作者 刘一阳 王子涵 +3 位作者 何梅 张承双 许海东 王明存 《陶瓷学报》 北大核心 2025年第6期1146-1156,共11页
本研究开发了一种经济型碳纤维网胎增强SiC复合材制备工艺。该技术采用机械混合法将乙烯基聚硅氮烷(ViLSZ,自制产品命名为PSZ-3112)基体树脂、碳化硅粉体与固化剂六亚甲基二异氰酸酯(HDI)混合制备成无溶剂浆料,以短切碳纤维网胎(C_(w))... 本研究开发了一种经济型碳纤维网胎增强SiC复合材制备工艺。该技术采用机械混合法将乙烯基聚硅氮烷(ViLSZ,自制产品命名为PSZ-3112)基体树脂、碳化硅粉体与固化剂六亚甲基二异氰酸酯(HDI)混合制备成无溶剂浆料,以短切碳纤维网胎(C_(w))为增强骨架,通过涂覆预浸—凝胶化—叠层—热压—烧结工艺流程成型复合材料。实验表明:HDI可有效催化ViLSZ树脂固化反应,其起始温度83.5℃,峰值温度118℃。最优工艺参数为:增强体C_(w)与浆料质量比1∶10,SiC/ViLSZ/HDI质量比1.0∶1.0∶0.2;凝胶过程在室温自发完成;热压阶段采用10 MPa压力、150℃温度环境。经高温烧结后,材料保持初始几何形态,密度≥1.75 g·cm^(-3),扫描电镜观测显示纤维—基体界面结合良好。最终材料摩擦系数为0.25~0.40,磨损率为0.12 cm^(3)·N^(-1)·m^(-1)~0.23 cm^(3)·N^(-1)·m^(-1)。结果表明,以聚硅氮烷为前驱体可实现陶瓷基复合材料的快速成型。 展开更多
关键词 短切碳纤维网胎 乙烯基聚硅氮烷 碳化硅陶瓷粉体 热压成型 陶瓷基复合材料
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短切玄武岩纤维掺量与长度对混凝土力学性能的影响研究
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作者 黄年进 胡朝斌 +2 位作者 马仪 李利平 何明剑 《工程技术研究》 2025年第6期102-105,共4页
玄武岩纤维能显著提升混凝土的抗压、抗折与抗拉强度,被广泛应用于建筑、交通等领域。就玄武岩纤维掺量与纤维长度等因素对混凝土性能的影响程度而言,不同的学者有不同的研究结果。文章通过开展不同纤维掺量与纤维长度的玄武岩纤维混凝... 玄武岩纤维能显著提升混凝土的抗压、抗折与抗拉强度,被广泛应用于建筑、交通等领域。就玄武岩纤维掺量与纤维长度等因素对混凝土性能的影响程度而言,不同的学者有不同的研究结果。文章通过开展不同纤维掺量与纤维长度的玄武岩纤维混凝土力学性能试验,分析纤维掺量与纤维长度对混凝土性能增强效果的影响,以供参考。 展开更多
关键词 短切玄武岩纤维 混凝土 纤维掺量 纤维长度
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一种具有不可恢复的过流保护电路设计
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作者 唐俊 徐立浩 +2 位作者 王喆 张心静 李晨洋 《集成电路与嵌入式系统》 2025年第10期61-65,共5页
为满足工业设备过流保护需求,提出一种基于模块化设计的电子电路解决方案,旨在实现精准电流检测与快速保护响应。采用模块化设计架构,集成电流感应放大器、迟滞比较器和继电器协同工作。通过电流感应放大器实现0.1 mA级精度信号采集,利... 为满足工业设备过流保护需求,提出一种基于模块化设计的电子电路解决方案,旨在实现精准电流检测与快速保护响应。采用模块化设计架构,集成电流感应放大器、迟滞比较器和继电器协同工作。通过电流感应放大器实现0.1 mA级精度信号采集,利用迟滞比较器设置保护阈值,配合固态继电器执行电路通/断控制。实验结果表明:当电流超过设定阈值时,电路在10 ms内完成切断动作,且在阈值电流下降到阈值电流以下仍保持断路状态,避免误恢复。经多次循环测试验证,保护动作准确率达98.4%,有效杜绝了因多次过流对设备造成的潜在损害,为高精度电流保护提供创新方案。 展开更多
关键词 过流保护 模块化设计 电流感应放大器 切断电流通路 保持短路状态
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短切煤沥青碳纤维的界面调控及电容脱盐协同增强机制
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作者 李赵悦 伊尔夏提·地力夏提 +2 位作者 古丽格娜·皮达买买提 白翔 罗新泽 《洁净煤技术》 北大核心 2025年第8期158-167,共10页
电容去离子(Capacitive Deionization,CDI)作为一种基于电场驱动离子电吸附的新型脱盐技术,因其低能耗和环境友好特性在水处理领域展现出重要应用前景。电极材料作为CDI系统的核心组件,其电子传导能力和界面润湿特性直接影响脱盐效率。... 电容去离子(Capacitive Deionization,CDI)作为一种基于电场驱动离子电吸附的新型脱盐技术,因其低能耗和环境友好特性在水处理领域展现出重要应用前景。电极材料作为CDI系统的核心组件,其电子传导能力和界面润湿特性直接影响脱盐效率。以高导电的短切煤沥青基碳纤维(Pitchbased Carbon Fiber,PCF)为对象,通过KOH化学活化构建分级孔结构以增加比表面积和采用硝酸氧化引入含氧官能团进行表面润湿性调控。经此双重活化制备的样品(KN-PCF),不仅比表面积高达583.83 m^(2)/g,而且接触角大幅降至65°,界面能显著降至34.6 mN/m(降幅达60.1%),还保持了优异的导电性(电导率约为13.7 S/cm)。在1.4 V低电压下,KN-PCF电极展现出25.5 mg/g的脱盐容量、0.77 Wh/g的能耗以及96.7%的脱盐容量保持率。结合密度泛函理论(DFT)计算揭示了KN-PCF表面含氧官能团通过降低Na+吸附能垒和缩小HOMO-LUMO能隙的双重机制,有效强化了离子捕获能力并提升了界面电荷转移效率。此外,通过COMSOL软件设计的三维多物理场仿真证实KN-PCF电极与电解液界面间的电场均匀性得到了显著提升。研究为低值沥青基碳纤维的高值化利用提供了理论和技术参考。 展开更多
关键词 短切煤沥青碳纤维 粗糙度 亲水性 电容脱盐 脱盐机理
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定尺剪自动定尺异常原因分析及控制措施
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作者 翟世宽 宋寅虎 +2 位作者 杨彦广 乔亚洲 杜晓月 《工业控制计算机》 2025年第2期154-156,共3页
某公司3500 mm中厚板剪切线通过切分段、切双边和切定尺完成整个剪切过程,激光测速仪应用后实现了定尺精度和剪切效率的提高,但在生产过程中偶尔会出现钢板切短问题。针对此问题,首先介绍了定尺剪本体结构和重要技术参数,阐述了激光测... 某公司3500 mm中厚板剪切线通过切分段、切双边和切定尺完成整个剪切过程,激光测速仪应用后实现了定尺精度和剪切效率的提高,但在生产过程中偶尔会出现钢板切短问题。针对此问题,首先介绍了定尺剪本体结构和重要技术参数,阐述了激光测速仪测长原理以及自动定尺剪切过程,进而分析了定尺剪应用激光测速仪后自动定尺异常原因,并提出了相应控制措施,提高了剪切合格率。 展开更多
关键词 中厚板 定尺剪 激光测速仪 自动定尺 切短
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尾巨桉-红锥混交复合生态营林模式下尾巨桉采伐强度对林下植物多样性的影响 被引量:1
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作者 吴衍霖 周晓果 +8 位作者 温远光 周雪梦 陈金磊 许峻模 杨婷 陈秋海 孙冬婧 黄勇杰 喻素芳 《广西科学》 北大核心 2025年第3期413-425,共13页
在桉树(Eucalyptus spp.)与珍贵乡土树种短中长周期复合经营中,短周期桉树采伐强度的确定对林分结构调整和林下植物多样性维持至关重要。为合理选择桉树采伐强度、优化林分结构、提高林下植物多样性,实现可持续经营,本研究以尾巨桉(Euca... 在桉树(Eucalyptus spp.)与珍贵乡土树种短中长周期复合经营中,短周期桉树采伐强度的确定对林分结构调整和林下植物多样性维持至关重要。为合理选择桉树采伐强度、优化林分结构、提高林下植物多样性,实现可持续经营,本研究以尾巨桉(Eucalyptus urophylla×E.grandis)-红锥(Castanopsis hystrix)混交林为研究对象,对林龄7 a的尾巨桉进行不同强度采伐[轻度采伐(LC,25%)、中度采伐(MC,50%)、重度采伐(HC,75%)和皆伐(CC,100%)],以未采伐的林分为对照(CK),研究不同尾巨桉采伐强度对林下植物多样性的影响,结果表明:①采伐尾巨桉改变了灌草层优势种的组成;灌木层中,林下植物多样性无显著差异;草本层中,中度采伐和皆伐显著提高物种丰富度和Simpson指数,中度采伐显著提高Shannon-Wiener指数。②轻度至重度采伐显著降低0-20 cm土层土壤有效氮含量,皆伐对土壤有效氮含量影响不显著;而中度采伐和皆伐显著提高0-20、20-40 cm土层土壤有机碳、全氮、全磷含量。③随着采伐强度的增加,林分叶面积指数表现为MC(4.58)>CC(4.23)>HC(4.20)>LC(3.86)>CK(3.79),但各采伐强度间差异不显著。④影响林下植物多样性的主控因子为土壤有机碳、有效氮、碳氮比和叶面积指数,其中土壤有机碳、叶面积指数与灌木层物种丰富度呈显著正相关,土壤有效氮、碳氮比与草本层物种丰富度呈显著正相关。综上所述,不同尾巨桉采伐强度对尾巨桉-红锥混交林林下植物群落物种多样性的影响不同,以中度采伐提升林下植物群落物种多样性、土壤养分含量的效果最佳。 展开更多
关键词 尾巨桉-红锥混交林 短中长周期复合经营 采伐强度 林下植被 物种多样性
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