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复合微生物制剂对猪舍空气质量的影响 被引量:3
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作者 王福厚 刘瑞生 +5 位作者 徐建峰 蒙琦 张新报 林欢庆 陈蓉蓉 胡仲军 《饲料研究》 CAS 北大核心 2022年第22期37-40,共4页
试验旨在研究复合微生物制剂对猪舍空气质量的影响。选择体重(8.50±0.57) kg的35日龄断奶仔猪225头,随机均分为5组,每组3个重复,每个重复15头猪。对照组猪饲喂基础日粮,常规饮水,猪舍不喷洒微生物制剂,试验1组在基础日粮中添加0.5... 试验旨在研究复合微生物制剂对猪舍空气质量的影响。选择体重(8.50±0.57) kg的35日龄断奶仔猪225头,随机均分为5组,每组3个重复,每个重复15头猪。对照组猪饲喂基础日粮,常规饮水,猪舍不喷洒微生物制剂,试验1组在基础日粮中添加0.5%复合微生物制剂A,试验2组在基础日粮中添加1.0%复合微生物制剂A,试验3组在基础日粮中添加0.5%复合微生物制剂B,试验4组在基础日粮中添加1.0%复合微生物制剂B,试验组均在饮水中添加1∶100比例稀释的小球藻悬浮液,猪舍内每隔2 d喷洒1次粪肠球菌和氯氰菊酯1∶50比例稀释液。预试期5 d,正式试验期30 d。结果显示:试验第20 d,试验2组、试验3组、试验4组猪舍氨气(NH3)浓度显著降低(P<0.05);试验第30 d,试验1组、试验2组、试验3组猪舍的NH3浓度显著降低(P<0.05),试验4组猪舍NH3浓度极显著降低(P<0.01)。与对照组相比,试验第10 d,各试验组猪舍硫化氢(H2S)浓度显著降低(P<0.05);试验第20和30 d,试验1组猪舍H2S浓度显著低降低(P<0.05),试验2组、试验3组、试验4组猪舍H2S浓度极显著降低(P<0.01)。与对照组相比,试验第10、20 d,各试验组猪舍蚊蝇密度均显著降低(P<0.05);试验第30 d,试验1组、试验2组、试验3组猪舍蚊蝇密度显著降低(P<0.05),试验4组猪舍蚊蝇密度极显著降低(P<0.01)。研究表明,复合微生物制剂可降低猪舍NH3和H2S浓度,减轻恶臭强度和蚊蝇密度,以添加1.0%复合微生物制剂B效果较好。 展开更多
关键词 微生物制剂 猪舍 空气质量 氨气 硫化氢 恶臭
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中草药添加剂对肉羊血清中酶活性影响的研究 被引量:5
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作者 徐建峰 刘瑞生 +4 位作者 王珂 陈万辉 薛春胜 张新报 谢文章 《畜牧兽医杂志》 2019年第3期8-10,共3页
采用单因子试验设计,分析了中草药添加剂对萨福克与小尾寒羊杂交一代羔羊血清中酶活性的影响。结果表明,在精料中添加1.5%中草药添加剂,在4个不同测定阶段,ALT、AST、γ-GT、CK和LDH活性,试验组均低于对照组,且组间差异不显著(P>0.05... 采用单因子试验设计,分析了中草药添加剂对萨福克与小尾寒羊杂交一代羔羊血清中酶活性的影响。结果表明,在精料中添加1.5%中草药添加剂,在4个不同测定阶段,ALT、AST、γ-GT、CK和LDH活性,试验组均低于对照组,且组间差异不显著(P>0.05);AKP活性,试验组显著高于对照组(P<0.05)。揭示了中草药添加剂对肉羊血清中酶活性具有一定影响。 展开更多
关键词 中草药 添加剂 肉羊 酶活性 生长发育
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船舶推进轴系振动对轴承承载特性的影响 被引量:2
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作者 张新宝 王鼎 《舰船科学技术》 北大核心 2019年第7期71-75,共5页
本文以某实际船舶推进轴系为研究对象,计入螺旋桨激振力大小和频率的影响,获得推进轴系发生振动时径向滑动轴承的承载状态,推导了径向润滑轴承承载力及液膜刚度的计算表达式,分析了螺旋桨激振力引起的推进轴系振动对径向润滑轴承承载特... 本文以某实际船舶推进轴系为研究对象,计入螺旋桨激振力大小和频率的影响,获得推进轴系发生振动时径向滑动轴承的承载状态,推导了径向润滑轴承承载力及液膜刚度的计算表达式,分析了螺旋桨激振力引起的推进轴系振动对径向润滑轴承承载特性的影响。结果表明,螺旋桨激振力会导致径向润滑轴承承载力及液膜刚度产生周期性的波动,不同加载频率前提下轴承承载特性表现各异,且重载条件下轴承承载特性的波动更为明显,必须合理设计轴承以提高轴承的承载能力,进而保证整个推进轴系的运行稳定性。 展开更多
关键词 推进轴系 径向滑动轴承 液膜刚度 承载特性
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可倾瓦推力轴承的分形表面形貌润滑性能研究
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作者 张新宝 范华显 《机械设计与制造》 北大核心 2021年第10期186-189,193,共5页
提出一种考虑表面形貌时可倾瓦推力轴承润滑特性的数值计算方法,采用分形函数重构了轴承润滑表面轮廓,并将表面轮廓参数整合到可倾瓦推力轴承润滑油膜的数值计算中,探索表面形貌变化对润滑特性影响。结果表明,随着尺度系数或分形维数增... 提出一种考虑表面形貌时可倾瓦推力轴承润滑特性的数值计算方法,采用分形函数重构了轴承润滑表面轮廓,并将表面轮廓参数整合到可倾瓦推力轴承润滑油膜的数值计算中,探索表面形貌变化对润滑特性影响。结果表明,随着尺度系数或分形维数增大,楔形油膜的厚度逐渐变小并且油膜的最大压力逐渐增大,油膜的压力分布波动越剧烈;当尺度系数改变时,油膜厚度和油压分布幅值变化,但分布趋势保持一致,分形维数则对其幅值和分布趋势都有影响;当分形参数变化时,轴承整体的承载能力和摩擦力出现波动,但波动很小。轴承表面形貌误差会对整个轴承的油膜的稳定性造成影响,因此在可倾瓦轴承的设计制造中要控制润滑表面的加工精度,保障可倾瓦推力轴承运行稳定。 展开更多
关键词 可倾瓦推力轴承 分形函数 表面形貌 润滑特性
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结核感染T细胞斑点试验联合胸腔积液Xpert MTB/RIF检测诊断结核性胸腔积液的价值 被引量:6
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作者 张新宝 张妍蓓 +3 位作者 姚超 洪青青 韩波波 张毕玲 《广东医学》 CAS 2020年第24期2564-2568,共5页
目的评估结核感染T细胞斑点试验(T-SPOT.TB)联合胸腔积液结核分枝杆菌/利福平耐药实时荧光定量核酸扩增检测技术(Xpert MTB/RIF)在结核性胸腔积液的诊断价值。方法收集胸腔积液患者112例,其中确诊或临床诊断为结核性胸腔积液76例,非结... 目的评估结核感染T细胞斑点试验(T-SPOT.TB)联合胸腔积液结核分枝杆菌/利福平耐药实时荧光定量核酸扩增检测技术(Xpert MTB/RIF)在结核性胸腔积液的诊断价值。方法收集胸腔积液患者112例,其中确诊或临床诊断为结核性胸腔积液76例,非结核性胸腔积液36例。所纳入患者治疗前均行胸腔积液T-SPOT.TB、血T-SPOT.TB、胸腔积液Xpert MTB/RIF、胸腔积液腺苷脱氨酶(ADA)检测,并对其检测结果进行分析。结果胸腔积液T-SPOT.TB诊断结核性胸腔积液的敏感度(97.37%,74/76),高于外周血T-SPOT.TB(76.32%,58/76)、胸腔积液Xpert MTB/RIF(65.79%,50/76)和胸腔积液ADA(28.95%,22/76),差异均有统计学意义(χ2=14.74、25.22、76.45,P<0.01)。胸腔积液Xpert MTB/RIF检测的特异度(100%,36/36)均高于胸腔积液T-SPOT.TB(77.78%,28/36)、外周血T-SPOT.TB(55.56%,20/36)和胸腔积液ADA(50.00%,18/36),差异均有统计学意义(χ2=6.89、20.57、24.00,P均<0.01)。胸腔积液T-SPOT.TB和胸腔积液Xpert MTB/RIF联合检测的敏感度(64.47%,49/76)低于胸腔积液T-SPOT.TB单独检测(97.37%,74/76),差异有统计学意义(χ2=26.63,P<0.01),但特异度由77.78%(28/36)提高至100%(36/36),差异有统计学意义(χ2=45.82,P<0.01)。结论胸腔积液T-SPOT.TB检测结核性胸腔积液具有较高的敏感度和特异度,胸腔积液T-SPOT.TB和胸腔积液Xpert Mtb/RIF联合检测可明显提高诊断的特异度。 展开更多
关键词 酶联免疫斑点试验 结核 胸腔积液 Xpert MTB/RIF 腺苷脱氨酶
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Assessing Soil Erosion Rates on Manually-Tilled Hillslopes in the Sichuan Hilly Basin Using ^(137)Cs and ^(210)Pb_(ex) Measurements 被引量:17
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作者 ZHENG Jin-Jun HE Xiu-Bin +3 位作者 D. WALLING zhang xin-bao D. FLANAGAN QI Yong- Qing 《Pedosphere》 SCIE CAS CSCD 2007年第3期273-283,共11页
Purple soils are widely distributed in the Sichuan Hilly Basin and are highly susceptible to erosion, especially on the cultivated slopes. Quantitative assessment of the erosion rates is, however, difficult due to sma... Purple soils are widely distributed in the Sichuan Hilly Basin and are highly susceptible to erosion, especially on the cultivated slopes. Quantitative assessment of the erosion rates is, however, difficult due to small size of the plots of the manually-tilled land, the complex land use, and steep hillslopes. ^137Cs and ^210Pbex (excess ^210Pb) tracing techniques were used to investigate the spatial pattern of soil erosion rates associated with slope-land under hoe tillage in Neijiang of the Sichuan Hilly Basin. The ^137Cs and ^210Pbex inventories at the top of the cultivated slope were extremely low, and the highest inventories were found at the bottom of the cultivated slope. By combining the erosion rates estimates provided by both ^137Cs and 21~Pbex measurements, the weighted mean net soil loss from the study slope was estimated to be 3 100 t km^-2 year^-1, which was significantly less than 6 930 t km^-2 year^-1 reported for runoff plots on a 10° cultivated slope at the Suining Station of Soil Erosion. The spatial pattern of soil erosion rates on the steep agricultural land showed that hoe tillage played an important role in soil redistribution along the slope. Also, traditional farming practices had a significant role in reducing soil loss, leading to a lower net erosion rate for the field. 展开更多
关键词 ^137CS hoe tillage ^210Pbex purple soil soil erosion
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Interpreting sedimentation dynamics at Longxi catchment in the Three Gorges Area,China,using Cs-137 activity,particle size and rainfall erosivity 被引量:6
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作者 GAO Jin-zhang LONG Yi +4 位作者 zhang xin-bao Collins Adrian L HE Xiu-bin zhang Yun-qi SHI Zhong-lin 《Journal of Mountain Science》 SCIE CSCD 2016年第5期857-869,共13页
Reservoir sedimentation dynamics were interpreted using Cs-137 activity, particle size and rainfall erosivity analysis in conjunetion with sediment profile coring. Two sediment cores were retrieved from the Changshou ... Reservoir sedimentation dynamics were interpreted using Cs-137 activity, particle size and rainfall erosivity analysis in conjunetion with sediment profile coring. Two sediment cores were retrieved from the Changshou reservoir of Chongqing, which was dammed in 1956 at the outlet of Longxi catchment in the Three Gorges Area using a gravity corer equipped with an aerylie tube with an inner diameter of 6 em. The extracted cores were sectioned at 2 cm intervals. All sediment core samples were dried, sieved (〈2 mm) and weighed. 137Cs activity was measured by y-ray spectrometry. The particle size of the core samples was measured using laser particle size granulometry. Rainfall erosivity was calculated using daily rainfall data from meteorological records and information on soil conservation history was collated to help interpret temporal sedimentation trends. The peak fallout of 137Cs in 1963 appeared at a depth of 84 cm in core A and 56 cm in core B. The peaks of sand contents were related to the peaks of rainfall erosivity which were recorded in 1982, 1989, 1998 and 2005, respectively. Sedimentation rates were calculated according to the sediment profile chronological controls of 1956, 1963, 1982, 1989, 1998 and 2oo5. The highest sedimentation rate was around 2.0 cm·a^-1 between 1982 and 1988 when the Chinese national reform and the Household Responsibility System were implemented, leading to accelerated soil erosion in the Longxi catchment. Since 1990s, and particularly since 2005, sedimentation rates clearly decreased, since a number of soil conservation programs have been carried out in the catchment. The combined use of ^137Cs chronology, particle size and rainfall erosivity provided a simple basis for reconstructing reservoir sedimentation dynamics in the context of both physical processes and soil restoration. Its advantages include avoiding the need for full blown sediment yield reconstruction and the concomitant consideration of core correlation and corrections for autochthonous inputs and reservoir trap efficiency. 展开更多
关键词 SEDIMENTATION Cesium-137 Particle size Rainfall erosivity Soil erosion Three Gorges Area
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Principal Denudation Processes and Their Contribution to Fluvial Suspended Sediment Yields in the Upper Yangtze River Basin and Volga River Basin 被引量:1
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作者 VALENTIN Golosov zhang xin-bao +2 位作者 HE Xiu-bin TANG Qiang ZHOU Ping 《Journal of Mountain Science》 SCIE CSCD 2015年第1期101-122,共22页
This paper synthesized the principal land denudation processes and their role in determining riverine suspended sediment yields(SSY) in two typical geographical environments of the Upper Yangtze River Basin in China a... This paper synthesized the principal land denudation processes and their role in determining riverine suspended sediment yields(SSY) in two typical geographical environments of the Upper Yangtze River Basin in China and the Volga River Basin in Eastern Europe. In the Upper Yangtze River Basin, natural factors including topography, climate,lithology and tectonic activity are responsible for the spatial variation in the magnitude of denudation rates.Human disturbances have contributed to the temporal changes of soil erosion and fluvial SSY during the past decades. On one hand, land use change caused by deforestation and land reclamation has played an important role in the acceleration of sediment production from the central hilly area and lower Jinsha catchment; On the other hand, diverse soil conservation practices(e.g., reforestation,terracing) have contributed to a reduction of soil erosion and sediment production since the late 1980 s.It was difficult to explicitly decouple the effect of mitigation measures in the Lower Jinsha River Basindue to the complexity associated with sediment redistribution within river channels(active channel migration and significant sedimentation). The whole basin can be subdivided into seven sub-regions according to the different proportional inputs of principal denudation processes to riverine SSY. In the Volga River Basin, anthropogenic sheet, rill and gully erosion are the predominant denudation processes in the southern region, while channel bank and bed erosion constitutes the main source of riverine suspended sediment flux in the northern part of the basin. Distribution of cultivated lands significantly determined the intensity of denudation processes.Local relief characteristics also considerably influence soil erosion rates and SSY in the southern Volga River Basin. Lithology, soil cover and climate conditions determined the spatial distribution of sheet, rill and gully erosion intensity, but they play a secondary role in SSY spatial variation. 展开更多
关键词 Land denudation Anthropogenicdisturbance Suspended sediment yield UpperYangtze River Volga River
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Historical Sediment Record of ^(137)Cs, δ-HCH, and δ^(13)C Reflects the Impact of Land Use on Soil Erosion 被引量:1
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作者 TANG Xiang-Yu zhang xin-bao +3 位作者 GUAN Zhuo LONG Yi TANG Qiang Lü Yu-Juan 《Journal of Mountain Science》 SCIE CSCD 2014年第4期866-874,共9页
This paper reports the concentrations of 137Cs, hexaehlorocyclohexane (HCH), dichlorodiphenyltrichloroethanes (DDT) and its main degradation products, δ3C, and organic carbon in pond sediments (O-210 cm, section... This paper reports the concentrations of 137Cs, hexaehlorocyclohexane (HCH), dichlorodiphenyltrichloroethanes (DDT) and its main degradation products, δ3C, and organic carbon in pond sediments (O-210 cm, sectioned by 2-20 cm interval) and surface soils (the 0-3 cm horizon) collected in 2OlO from Chenjia catchment, which is located in Yanting county in the hilly central Sichuan of China. α-, β-, and γ-HCH, DDT, and DDD were not detected throughout the sediment profile. Trace concentrations of δ-HCH (0.89-29.31 ng g^-1) and p,p'- DDE (1.85-6.02 ng g^-1) were detected only in top 40 cm sediment. The 137Cs fallout peak in 1963 (corresponding to the 55-60 cm depth), the sedimentary signature left by the last year of HCH use in 1989 (an additional indicator at 20-25 cm), and the obvious original channel bed prior to the construction of the pond in 1956 were used as temporal markers to estimate changes in average sedimentation rate between different periods due to changes in land use. Continuous, marked decrease in average sedimentation rate (i.e., 3.79, 1.35 and 1.07 cm year-1 in 1956-1963, 1963-1989, and 1989-2010, respectively) over time was observed, probably due to the reforestation, abandoning of steep sloping farmland for afforestation and natural re-vegetation (implementation of the Grain for Green Program), and the conversion of part of gently sloping farmlandterraces to orchard land since the 1980s, especially since the 1990s. This was corroborated by the observed decrease (more negative) in δ3C of sediment towards the surface, which indicates increased relative contribution of eroded soil particles coming from slopes with increased tree cover in sediment source area. Combined use of 137Cs, δ-HCH, and δ3C record in sediments has been demonstrated to be a powerful approach to reconstruction of response in sedimentation rate to historical land use changes. 展开更多
关键词 Cesium-137 Hexaehlorocyclohexane(HCH) Sedimentation history Land use
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Variation of soil organic carbon and bulk density during afforestation regulates soil hydraulic properties
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作者 GU Feng CHEN Xue-jiao +2 位作者 SU Zheng-an zhang xin-bao ZHOU Ming-hua 《Journal of Mountain Science》 SCIE CSCD 2022年第8期2322-2332,共11页
Grain to Green program on arable land has been conducted for decades in semi-arid regions of North China.However,it remains uncertain how afforestation practices affect soil hydraulic properties(SHP).Two afforestation... Grain to Green program on arable land has been conducted for decades in semi-arid regions of North China.However,it remains uncertain how afforestation practices affect soil hydraulic properties(SHP).Two afforestation types,i.e.shrubland(SL)and woodland(WL),and the adjacent cropland(CL)were investigated to determine afforestation effects on SHP in this area.Disturbed and undisturbed soil cores were collected in three experimental sites.Soil field capacity(FC),wilting point(WP),and available water capacity(AWC)increased in SL compared to the CL.Soil saturated water content,however,decreased significantly in both SL and WL.Correlation and redundancy analysis identified that bulk density(BD)and soil organic carbon(SOC)were the main factors regulating SHP across different land uses.Lower saturated water contents in afforestation sites were likely driven by the higher BD,compared to the adjacent cropland.FC,WP,and AWC were positively correlated to SOC content.While afforestation may not increase the saturated water content of a landscape,our results indicate that it can improve soil water retention and could be an effective practice for soil and water conservation. 展开更多
关键词 AFFORESTATION Bulk density Field capacity Soil hydraulic properties Soil organic carbon Soil water retention curve
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TFCP2L1在子宫内膜癌细胞增殖及侵袭中的作用
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作者 罗伊凡 余力 +5 位作者 楼利群 吕牧 余娟娟 张新宝 张箴波 覃祚树 《现代生物医学进展》 CAS 2024年第10期1801-1806,共6页
目的:研究人子宫内膜癌中TFCP2L1的表达情况以及分析TFCP2L1对子宫内膜癌细胞增殖及迁移能力的影响。方法:(1)通过TCGA及GTEx数据库分析子宫内膜癌中TFCP2L1的表达水平及患者生存期。采用Western blot验证正常子宫内膜上皮细胞与多种子... 目的:研究人子宫内膜癌中TFCP2L1的表达情况以及分析TFCP2L1对子宫内膜癌细胞增殖及迁移能力的影响。方法:(1)通过TCGA及GTEx数据库分析子宫内膜癌中TFCP2L1的表达水平及患者生存期。采用Western blot验证正常子宫内膜上皮细胞与多种子宫内膜癌细胞系中TFCP2L1的表达情况。(2)使用CRISPR-Cas9技术敲除Ishikawa细胞系的TFCP2L1,并用流式分选技术筛选单个细胞进行培养,形成单克隆细胞系,以此来研究TFCP2L1对子宫内膜癌的细胞周期和细胞增殖的影响。通过Western blot及细胞免疫荧光检测细胞周期相关蛋白的表达,检测细胞增殖情况,采用平板克隆实验及CCK8实验。(3)通过Transwell小室及划痕实验对侵袭和转移能力进行检测。结果:TCGA及GTEx数据库分析发现TFCP2L1在子宫内膜癌中高表达且与肿瘤患者预后不良相关。敲除TFCP2L1后,Ki67、Cyclin D1和Cyclin D2的蛋白水平显著下调,CCK8及平板克隆实验结果表明,敲除TFCP2L1能够显著降低子宫内膜癌细胞的增殖能力。划痕实验及Transwell侵袭实验结果表明敲除TFCP2L1的子宫内膜癌细胞侵袭迁移能力均减弱。结论:本研究证明了TFCP21L1是子宫内膜癌的促癌因子。TFCP2L1的高表达可能与子宫内膜癌预后不良相关。敲除TFCP2L1可以抑制子宫内膜癌的侵袭和转移。 展开更多
关键词 TFCP2L1 子宫内膜癌 细胞周期 细胞增殖 细胞迁移
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^(137)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest China 被引量:3
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作者 LI Hao zhang xin-bao +1 位作者 WANG Kc-Lin WEN An-Bang 《Pedosphere》 SCIE CAS CSCD 2011年第1期37-45,共9页
The fallout radionuclide cesium-137(137 Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by ... The fallout radionuclide cesium-137(137 Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst areas.Information derived from 137 Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 137 Cs redistribution in a karst area of Southwest China.The results indicated that the 137 Cs inventories of the surface soil on the slope studied were much lower than that of the local 137 Cs reference inventory and the 137 Cs activities were much higher than those on slopes with thick uniform soils.The spatial distribution of 137 Cs inventories was characterized by considerable variation.The high 137 Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 137 Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 137 Cs.These demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 137 Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils. 展开更多
关键词 carbonate dissolution ^137Cs fallout ^137Cs inventory karst area RUNOFF
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