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低洼重度盐碱地滴灌水盐调控的环境效应 被引量:9
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作者 万书勤 孙甲霞 +1 位作者 董世德 康跃虎 《干旱地区农业研究》 CSCD 北大核心 2019年第1期1-10,共10页
采用"咸水滴灌+高垄+覆膜"水盐调控技术模式,开发利用河套灌区水平排水困难的低洼重度盐碱撂荒地时,研究了该区浅层地下水埋深、浅层地下水电导率(ECw)、潜水层地下水电导率(ECi)、土壤饱和泥浆提取液电导率(ECe)、枸杞成活... 采用"咸水滴灌+高垄+覆膜"水盐调控技术模式,开发利用河套灌区水平排水困难的低洼重度盐碱撂荒地时,研究了该区浅层地下水埋深、浅层地下水电导率(ECw)、潜水层地下水电导率(ECi)、土壤饱和泥浆提取液电导率(ECe)、枸杞成活率和保存率等的变化。结果表明:研究区浅层地下水埋深、ECw和ECe明显受周边和研究区灌溉、降雨等的影响;随着枸杞种植年限的延长及植株蒸腾耗水的增加,整个研究区的浅层地下水埋深、ECw、ECi及ECe均逐年降低,0~40 cm土层土壤由极重度盐土转变为重度盐土;该技术模式下,枸杞成活率达到75.4%,保存率达到67.5%。即可以采用"咸水滴灌+高垄+覆膜"滴灌水盐调控技术模式,通过种植枸杞等耐盐碱的多年生林果,来开发利用传统方法难以有效开发利用的地下水浅埋且地下水为咸水的重度盐碱地,通过枸杞生长耗水可以显著降低整个区域的地下水位埋深,ECw和ECe也逐年降低。 展开更多
关键词 低洼盐碱地 地下水浅埋区 浅层地下水埋深 地下水电导率 潜水层地下水电导率 土壤饱和泥浆提取液电导率
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滴灌施肥条件下减量施肥对马铃薯田土壤养分积累及产量的影响 被引量:11
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作者 冯志文 万书勤 +2 位作者 康跃虎 孙清华 张若芳 《节水灌溉》 北大核心 2019年第8期28-33,38,共7页
为了进一步确定合理施肥量并有效指导滴灌条件下的肥料管理,以马铃薯“夏波蒂”为试材,基于推荐施肥量(N、P2O5、K2O施用量分别为420、105、495kg/hm^2),布置了5个施肥量比例的滴灌施肥灌溉处理,分别为推荐施肥量的10%(F1)、30%(F2)、50... 为了进一步确定合理施肥量并有效指导滴灌条件下的肥料管理,以马铃薯“夏波蒂”为试材,基于推荐施肥量(N、P2O5、K2O施用量分别为420、105、495kg/hm^2),布置了5个施肥量比例的滴灌施肥灌溉处理,分别为推荐施肥量的10%(F1)、30%(F2)、50%(F3)、70%(F4)和90%(F5),研究了其对收获时农田土壤养分积累与产量的影响。结果表明,经过整个生育期的滴灌施肥灌溉后,随着施肥量的增加,0~60cm土层的硝态氮浓度增加,且向土壤下层的移动增加;0~40cm土层的铵态氮浓度和0~30cm土层的速效磷浓度呈先增加后下降的趋势;0~60cm土层的速效钾浓度在垂直分布减弱,而水平分布增加。当施肥量比例在70%左右(F4)时,土壤养分主要在积累0~40cm土层,且向下层土壤淋失较少。马铃薯产量随着施肥量的增加呈先增加后下降的趋势,以F3处理最高,为25.3t/hm^2,除显著高于F1处理外,与其他处理间差异不显著。因此,滴灌施肥灌溉时,当施肥量比例为推荐施肥量的70%左右时,马铃薯田的土壤养分主要积累在0~40cm土层,并降低了施肥量、减少了养分从根区的淋失,且产量较高。 展开更多
关键词 滴灌施肥 马铃薯 施肥量比例 土壤养分积累
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一种用于JESD204B协议的8B/10B并行编码电路设计与实现 被引量:3
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作者 王俊杰 万书芹 +2 位作者 季惠才 陶建中 杨阳 《微电子学与计算机》 北大核心 2020年第6期35-39,共5页
本文设计并实现了一种四路并行的8B/10B编码电路,通过了NCVerilog仿真验证,在某65nm工艺库下工作频率可达405MHz,可支持16.2Gbps的串行数据传输速率,占用逻辑资源面积1832μm^2,并作为JESD204B协议中的8B/10B编码模块已应用于某高速ADC... 本文设计并实现了一种四路并行的8B/10B编码电路,通过了NCVerilog仿真验证,在某65nm工艺库下工作频率可达405MHz,可支持16.2Gbps的串行数据传输速率,占用逻辑资源面积1832μm^2,并作为JESD204B协议中的8B/10B编码模块已应用于某高速ADC芯片的SerDes接口电路中.经实际电路测试,本设计达到了JESD204B协议标准的12.5Gbps最高传输速率要求. 展开更多
关键词 JESD204B 8B/10B编码 四路并行 SERDES
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微喷带施肥灌溉对小麦玉米产量和水肥利用的影响 被引量:12
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作者 白珊珊 万书勤 +1 位作者 康跃虎 焦艳平 《节水灌溉》 北大核心 2019年第3期1-7,共7页
在2013-2015年两个连续的冬小麦-夏玉米生育期内,选用带宽为65 cm的双翼型微喷带,底肥(种肥)选用控失肥,总施肥量为当地地面灌溉高产推荐施肥量的70%,作物生育季当20 cm深度土壤基质势降低到-40 kPa时进行施肥灌溉,因夏玉米生育期正值雨... 在2013-2015年两个连续的冬小麦-夏玉米生育期内,选用带宽为65 cm的双翼型微喷带,底肥(种肥)选用控失肥,总施肥量为当地地面灌溉高产推荐施肥量的70%,作物生育季当20 cm深度土壤基质势降低到-40 kPa时进行施肥灌溉,因夏玉米生育期正值雨季,除播种后灌溉,大喇叭口期和花粒期主要采用微喷带进行追肥。试验结果表明:①微喷带施肥灌溉水肥一体化可分别提高冬小麦和夏玉米的产量7.9%和17.1%;②冬小麦总耗水量平均为439.6 mm。整个生育期灌水量所占的比例最大,平均为36.4%,其次是土壤储水量的消耗量(35.6%),降水量占总耗水量的23.7%,地下水的补给量占的比例最小,仅4.3%。冬小麦水分利用效率平均达到1.7 kg/m^3,提高了21%。0~50 cm土壤储水量的消耗量占整个土层土壤储水量的消耗量最大,高达40%。③冬小麦和夏玉米的灌溉水利用效率分别平均为4.5和13.8 kg/m^3,分别提高了103%和62%,N和P的肥料偏生产力分别均提高了58%和67%。土壤养分主要分布在0~40 cm土层内,100~140 cm土层硝态氮含量降低了92%,显著减少了养分淋失,有效提高了肥料利用效率。因此华北平原地区微喷带施肥灌溉可提高冬小麦夏玉米的产量、水分利用效率、灌溉水利用效率和肥料利用效率。 展开更多
关键词 土壤基质势 施肥灌溉制度 耗水规律 水分利用效率 肥料偏生产力
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基于精确频率控制字的高速DDS电路设计与实现 被引量:1
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作者 杨阳 陶建中 +1 位作者 万书芹 邱丹 《电子设计工程》 2020年第3期5-8,13,共5页
针对传统直接数字频率合成器(DDS)的频率控制字FTW必须为一个整数值,而不能为小数的情况,提出一种可编程调制的DDS电路设计。该电路结构在已有相位累加器的基础上,增加一个辅助累加器用于改变DDS内核的频率方程,使得频率控制字FTW可以... 针对传统直接数字频率合成器(DDS)的频率控制字FTW必须为一个整数值,而不能为小数的情况,提出一种可编程调制的DDS电路设计。该电路结构在已有相位累加器的基础上,增加一个辅助累加器用于改变DDS内核的频率方程,使得频率控制字FTW可以是小数成为可能,提高了DDS的输出频率精度。并对传统Cordic算法进行了改进,降低了运算复杂度,减少了相幅转换的时间,节约了硬件资源。 展开更多
关键词 直接数字频率合成 频率控制字 精度 CORDIC算法 改进
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Effects of water application intensity of microsprinkler irrigation on water and salt environment and crop growth in coastal saline soils 被引量:4
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作者 CHU Lin-lin KANG Yao-hu wan shu-qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第10期2077-2089,共13页
Laboratory and field experiments were conducted to investigate the effects of water application intensity(WAI) on soil salinity management and the growth of Festuca arundinacea(festuca) under three stages of water... Laboratory and field experiments were conducted to investigate the effects of water application intensity(WAI) on soil salinity management and the growth of Festuca arundinacea(festuca) under three stages of water and salt management strategies using microsprinkler irrigation in Hebei Province, North China. The soil water content(è) and salinity of homogeneous coastal saline soils were evaluated under different water application intensities in the laboratory experiment. The results indicated that the WAI of microsprinkler irrigation influenced the è, electrical conductivity(ECe) and p H of saline soils. As the WAI increased, the average values of è and ECe in the 0–40 cm profile also increased, while their average values in the 40–60 cm profile decreased. The p H value also slightly decreased as depth increased, but no significant differences were observed between the different treatments. The time periods of the water redistribution treatments had no obvious effects. Based on the results for è, ECe and p H, a smaller WAI was more desirable. The field experiment was conducted after being considered the results of the technical parameter experiment and evaporation, wind and leaching duration. The field experiment included three stages of water and salt regulation, based on three soil matric potentials(SMP), in which the SMP at a 20-cm depth below the surface was used to trigger irrigation. The results showed that the microsprinkler irrigation created an appropriate environment for festuca growth through the three stages of water and salt regulation. The low-salinity conditions that occurred at 0–10 cm depth during the first stage(-5 k Pa) continued to expand through the next two stages. The average p H value was less than 8.5. The tiller number of festuca increased as SMP decreased from the first stage to the third stage. After the three stages of water and salt regulation, the highly saline soil gradually changed to a low-saline soil. Overall, based on the salt desalinization, the microsprinkler irrigation and three stages of water and salt regulation could be successfully used to cultivate plants for the reclamation of coastal saline land in North China. 展开更多
关键词 coastal saline soil microsprinkler irrigation water application intensity soil salinity water and salt regulation RECLAMATION
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Effect of different water application intensity and irrigation amount treatments of microirrigation on soil-leaching coastal saline soils of North China 被引量:3
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作者 CHU Lin-lin KANG Yao-hu wan shu-qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第9期2123-2131,共9页
In coastal regions, Bohai Gulf is one of the most affected areas by salinization. To study the effects of mocrosprinkler irrigation on the characteristics of highly saline sandy loam soil(ECe(saturated paste extract... In coastal regions, Bohai Gulf is one of the most affected areas by salinization. To study the effects of mocrosprinkler irrigation on the characteristics of highly saline sandy loam soil(ECe(saturated paste extract)=22.3 d S m^–1; SAR(sodium adsorption ratio)=49.0) of North China, a laboratory experiment was conducted. Five water application intensity(WAI) treatments(1.7, 3.1, 5.3, 8.8, and 10.1 mm h^–1), five irrigation amount(IA) treatments(148, 168, 184, 201, and 223 mm) and three time periods of water redistribution(0, 24 and 48 h) were employed in the study. A compounding microsprinkler system was used for the WAI treatments, and a single microsprinkler was used for the IA treatments. The results indicated that, as soil depth increased, soil water content(θ) increased and then slightly decreased; with WAI and IA consistently increasing, the relatively moist region expanded and the average θ increased. Meanwhile, soil ECe increased as soil depth increased, and the zone with low soil salinity expanded as WAI and IA increased. Although the reduction of the average SAR was smaller than that of the average electrical conductivity of the ECe, these variables decreased in similar fashion as WAI and IA increased under microsprinkler irrigation. The average p H decreased as soil depth increased. Longer time periods of water redistribution led to lower salinity and slight expansion of the SAR zone. Considering the effects of leached salts in coastal saline soils, greater WAI and IA values are more advantageous under unsaturated flow conditions, as they cause better water movement in the soil. After leaching due to microsprinkler irrigation, highly saline soil gradually changes to moderately saline soil. The results provide theoretical and technological guidance for the salt leaching and landscaping of highly saline coastal environments. 展开更多
关键词 coastal saline soil microsprinkler irrigation SAR reclamation
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纳布啡复合丙泊酚用于老年高血压患者胃肠镜检查术的效果观察 被引量:3
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作者 万淑琴 古德华 《黑龙江医学》 2020年第9期1232-1234,共3页
目的探讨纳布啡复合丙泊酚用于老年高血压患者胃肠镜检查的效果及安全性。方法选择ASAⅡ级行胃肠镜检查老年高血压患者80例。随机分为纳布啡组(N组)和芬太尼组(F组),每组各40例。N组采用静注纳布啡0.1 mg/kg复合丙泊酚麻醉;F组采用静注... 目的探讨纳布啡复合丙泊酚用于老年高血压患者胃肠镜检查的效果及安全性。方法选择ASAⅡ级行胃肠镜检查老年高血压患者80例。随机分为纳布啡组(N组)和芬太尼组(F组),每组各40例。N组采用静注纳布啡0.1 mg/kg复合丙泊酚麻醉;F组采用静注芬太尼1 ug/kg复合丙泊酚麻醉。观察并记录诱导前(T0)、诱导后(T1)、内镜置入时(T2)两组患者的心率(HR)、平均动脉压(MAP)、血氧饱和度(SpO2);记录两组丙泊酚的诱导用量、苏醒时间及术后腹痛情况;并记录两组患者循环及呼吸抑制、呛咳、体动、恶心呕吐等不良反应发生情况。结果与T0时比较,T1、T2时点N组HR、MAP、SpO2稍有下降(P>0.05),F组HR、MAP、SpO2明显下降(P<0.05);组间比较N组T1、T2时点HR、MAP、SpO2明显高于F组(P<0.05),N组丙泊酚用量明显少于F组(P<0.05),苏醒时间稍长于F组(P>0.05),术后腹痛评分明显低于F组(P<0.05)。N组低MAP、低SpO2、呛咳及体动的发生率明显低于F组(P<0.05)。结论纳布啡复合丙泊酚用于老年高血压患者胃肠镜检查安全有效,能减少丙泊酚用量,与芬太尼相比,呼吸循环更平稳,在保证麻醉效果的同时,能减少术中不良反应的发生,减轻操作引起的内脏痛,提高检查的安全性和舒适性。 展开更多
关键词 纳布啡 丙泊酚 高血压 胃肠镜检查
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Comparison of Two Dripper Line Designs to Assess Cotton Yield,Water Use,and Net Return in Northwest China
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作者 wanG Ruo-shui wan shu-qin +1 位作者 KANG Yue-hu LIU Shi-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第11期1924-1932,共9页
This study aimed to compare the effects of two types of drip irrigation line design on cotton yield, water use, and net returns. The experiments were carried out in the arid region of Xinjiang, Northwest China, during... This study aimed to compare the effects of two types of drip irrigation line design on cotton yield, water use, and net returns. The experiments were carried out in the arid region of Xinjiang, Northwest China, during 2009-2010 growing years. The two types of lateral placement are commonly used by the local farmers in the area: double lines (two laterals controlling four rows) and single line designs (one lateral controlling four rows). The results indicated that less irrigation water was applied by single line compared with double lines design. This implies that more irrigation water could be saved using single line, by reducing the water consumption of cotton. The emergence rates for double lines were 2 and 6% higher than those for single line design in 2009 and 2010. The seed cotton yields for double lines design were 5.76 and 6.41 Mg ha-1 which were 13 and 9% higher than for single line design in 2009 and 2010, respectively. Single lines could however lower the investment cost compared to double lines, which produced 10 and 7% more net income in 2009 and 2010, respectively. By contrast, the double lines was more profitable and suitable for the farmers in Northwest China than single line design. 展开更多
关键词 drip irrigation lateral layout economic benefit water saving water use efficiency (WUE)
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滴灌条件下散水介质规格对龟裂碱土水盐运移特征的影响
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作者 黄鹏飞 黄艳丽 +3 位作者 康跃虎 万书勤 李晓彬 刘春成 《土壤通报》 CAS CSCD 北大核心 2024年第4期944-952,共9页
【目的】探讨滴灌改良利用龟裂碱土方法中散水介质规格对剖面水盐运移特征的影响,研究结果为散水介质规格的选择提供科学依据。【方法】通过室内土柱模拟试验,在一维和二维条件下对比分析了不同散水介质规格对龟裂碱土水盐运移特征的影... 【目的】探讨滴灌改良利用龟裂碱土方法中散水介质规格对剖面水盐运移特征的影响,研究结果为散水介质规格的选择提供科学依据。【方法】通过室内土柱模拟试验,在一维和二维条件下对比分析了不同散水介质规格对龟裂碱土水盐运移特征的影响。【结果】一维垂直入渗条件下,平铺型散水介质的深度在0~10 cm越小或10~15 cm越大,均能获得较高的垂直湿润峰扩散速度,随散水介质深度减小,灌水频率增加,促进了盐分淋洗。二维入渗条件下,垂直湿润峰入渗速率大于水平湿润峰入渗速率,稳定入渗阶段两者均随半球型散水介质直径的增加而下降,但单位灌溉水盐分淋洗效率降低,单位时间盐分淋洗效率不变,散水介质直径≥20 cm时水分扩散速率变化趋缓。【结论】不同散水介质规格改变了灌水频率和单次灌水量,进而影响龟裂碱土的水分入渗和盐分淋洗过程。实际应用中在考虑灌溉水淋洗效率的同时要兼顾经济效益,满足一年生植物生长需求后散水介质深度越小越好,而多年生作物采用半球型散水介质时直径不易超过20 cm。 展开更多
关键词 盐碱地改良 龟裂碱土 滴灌 散水介质 水盐运移
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散水介质滴灌龟裂碱土水盐运移规律 被引量:1
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作者 黄鹏飞 康跃虎 +3 位作者 万书勤 李晓彬 黄艳丽 刘春成 《土壤通报》 CAS CSCD 北大核心 2023年第5期1041-1049,共9页
【目的】探究散水介质滴灌条件下龟裂碱土水盐运移规律。【方法】室内设置土柱试验研究散水介质滴灌条件下龟裂碱土水分、电导率和pH的变化规律。【结果】一维垂直入渗条件下散水介质滴灌较定水头入渗水分扩散速率更快,稳定入渗阶段散... 【目的】探究散水介质滴灌条件下龟裂碱土水盐运移规律。【方法】室内设置土柱试验研究散水介质滴灌条件下龟裂碱土水分、电导率和pH的变化规律。【结果】一维垂直入渗条件下散水介质滴灌较定水头入渗水分扩散速率更快,稳定入渗阶段散水介质滴灌垂直湿润峰扩散速率提高了50.3%,两种灌溉方式水盐分布规律基本一致。二维条件下垂直方向湿润峰扩散速率高于水平方向,水分再分布过程中以散水介质和龟裂碱土界面处碱土表层土壤为中心向外扩散;散水介质水平距离10 cm时,相邻灌水器形成的湿润体在96 h逐渐搭接整体向外淋洗盐分;电导率<2 dS m^(-1)的脱盐区pH<9,电导率介于2~4 dS m^(-1)的脱盐区土壤pH值较原土逐渐降低,脱盐区边缘电导率介于4~10 dS m^(-1),pH值显著高于原土,积盐区边缘pH值较原土略下降。【结论】散水介质滴灌能够显著增加龟裂碱土的水分入渗速率,并在灌水器下方快速形成脱盐区,脱盐初期土壤碱化现象明显且与脱盐程度密切相关,生产实践中应采取相应的措施避免pH值过高影响植物生长。 展开更多
关键词 盐碱地改良 龟裂碱土 滴灌 散水介质 水盐运移
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Soil Salinity Changes Under Cropping with Lycium barbarum L.and Irrigation with Saline-Sodic Water 被引量:12
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作者 DOU Chao-Yin KANG Yao-Hu +1 位作者 wan shu-qin HU Wei 《Pedosphere》 SCIE CAS CSCD 2011年第4期539-548,共10页
In order to utilize the wasted saline-sodic soils under shallow groundwater condition, a 3-year field study was carried in a field cropped with Lycium barbarum L. and irrigated by drip irrigation with saline groundwat... In order to utilize the wasted saline-sodic soils under shallow groundwater condition, a 3-year field study was carried in a field cropped with Lycium barbarum L. and irrigated by drip irrigation with saline groundwater under the water table depth of 30-40 cm in the northern Yinchuan Plain, China. Effects of cropping duration (one, two, and three years) on soil salinity, soil solution composition, and pH in three adjacent plots were investigated in 2008. Results showed that a high irrigation frequency maintained high soil water potential and subsequently facilitated infiltration and downward movement of water and salt in the crop root zone. Salt accumulated on the edges of the ridges, and soil saturated-paste electrical conductivity (ECe) was higher in the edge. Concentrations of Na^+, Ca^2+, Mg^2+, Cl^-, and SO24^- in the soil increased with the soil depth as did the ECe, while HCO3 and pH had a relative uniform distribution in soil profile. As planting year increased, the ECe and soil salts in the field had a decreasing tendency, while in the root zone they decreased immediately after irrigation and then remained relatively stable in the following growing seasons. HCO3 and pH had little change with the planting year. Results suggested that the application of drip irrigation with saline water could ameliorate saline-sodic soil and provide a relatively feasible soil environment for saline-sodic soils with shallow groundwater. 展开更多
关键词 water table the growth of salt-tolerant plant Lycium barbarum L. under the salt accumulation saturated-paste electrical conductivity (ECe) shallow groundwater soil water potential depth
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