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国内常用脱酸工艺、特点与脱酸对象的选择 被引量:2
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作者 刘家真 《图书馆杂志》 北大核心 2024年第3期109-115,共7页
本文论述了脱酸对象的选择原则与脱酸过程中存在的风险,并结合中国国情给出了需优先脱酸的对象、脱酸过程中可能存在风险而需要谨慎处置的对象,以及不宜脱酸的对象。对国内使用较为广泛的脱酸技术进行了分析,包括同类比较与差异性分析,... 本文论述了脱酸对象的选择原则与脱酸过程中存在的风险,并结合中国国情给出了需优先脱酸的对象、脱酸过程中可能存在风险而需要谨慎处置的对象,以及不宜脱酸的对象。对国内使用较为广泛的脱酸技术进行了分析,包括同类比较与差异性分析,并以咨询的方式给出了脱酸用户所关切的信息。 展开更多
关键词 脱酸目的 脱酸工艺 脱酸风险 非水分散体脱酸 碱水脱酸 等离子碱雾脱酸
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基于近场动力学的爆炸抛撒研究
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作者 石玥 张光鹏 +2 位作者 齐健 李文超 李保伟 《机械设计与制造工程》 2023年第4期87-92,共6页
有限元方法在处理复杂裂纹问题时存在固有缺陷,基于非局部理论的近场动力学弥补了这一短板。为了将近场动力学方法应用于爆炸抛撒研究,针对固体燃料爆炸抛撒问题,采用近场动力学键理论,在合理假设的基础上提出了基于近场动力学的二维爆... 有限元方法在处理复杂裂纹问题时存在固有缺陷,基于非局部理论的近场动力学弥补了这一短板。为了将近场动力学方法应用于爆炸抛撒研究,针对固体燃料爆炸抛撒问题,采用近场动力学键理论,在合理假设的基础上提出了基于近场动力学的二维爆炸抛撒模型。进一步基于MATLAB平台开发了数值计算程序,并验证了程序在预测抛撒药云雾分布方面的有效性。最后研究了圆形、方形中心装药结构对爆炸抛撒结果的影响。仿真结果表明:程序所得16 ms内云雾分布形状及2 ms内云雾扩散速率较为准确;不同装药结构会影响云雾扩散速度及云雾分布形状;圆形装药更有利于抛撒药的分散。 展开更多
关键词 近场动力学 爆炸抛撒 云雾分布 非局部理论 中心装药结构
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Vegetative propagation of Litsea monopetala, a wild tropical medicinal plant: Effects of indole-3-butyric acid (IBA) on stem cuttings 被引量:12
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作者 Tarit Kumar Baul Mohammad Mosharraf Hossain +1 位作者 Mohammad Mezbahuddin Mohammed Mohiuddin 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期409-416,共8页
In this study we investigated the rooting ability and the growth performance of juvenile single-node leafy stem cuttings of Litsea monopetala (Roxb) Pers. collected from two mature mother trees preserved in the hill... In this study we investigated the rooting ability and the growth performance of juvenile single-node leafy stem cuttings of Litsea monopetala (Roxb) Pers. collected from two mature mother trees preserved in the hill forest of Chittagong district, Bangladesh. The rooting ability of cuttings was studied under 0%, 0.1%, 0.2% and 0.4% indole-3-butyric acid (IBA) treatments. Significantly better rooting response (p ≤ 0.05) was observed with 0.1% IBA compared to control (0% IBA). The mean number of roots and the length of the longest root of cuttings in different treatments showed no significant difference (p≤0.05). After transfer into polythene bags from non-mist propagator, rooted cuttings treated with 0%, 0.1% and 0.2% IBA demonstrated the highest (100 ± 0.00%) survival capacity. The mean number of shoots developed in cuttings in the polythene bags in first three weeks varied significantly (p≤0.05) among the treatments. Effects of three fertilizer treatments, viz. T0 (no fertilizer), T1 (10g Urea, 20g TSP, 10g MOP dissolved in 1 L water) and T2 (10g Urea, 20g TSP, 10g MOP dissolved in 2 L water) on initial growth ofstecklings were also measured over a 90-days period. The increment of leaf area of stecklings was significantly higher (p≤0.05) under T0 compared with that under T1 and T2 while the increment of stem length, collar diameter and root biomass varied insignificantly among different fertilizer treatments. The results suggest that rooting juvenile single-node leafy stem cuttings could be an effective mean of regenerating L. monopetala. The application of 0.1% IBA concentration is recommended for rooting of juvenile leafy stem cuttings and application of fertilizer appeared unnecessary for the subsequent growth of stecklings in polythene bags. 展开更多
关键词 IBA Litsea monopetala non-mist propagator ROOTING stem cutting
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Clonal propagation of Bambusa vulgaris by leafy branch cuttings 被引量:2
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作者 M.S. Islam M.K. Bhuiyan +1 位作者 M. M. Hossain M.A. Hossain 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期387-392,共6页
Bambusa vulgaris Schrad ex wendl is a widely cultivated bamboo species in rural Bangladesh for its versatile uses. The vegetative propagation becomes the only viable alternative for this species because B. vulgaris do... Bambusa vulgaris Schrad ex wendl is a widely cultivated bamboo species in rural Bangladesh for its versatile uses. The vegetative propagation becomes the only viable alternative for this species because B. vulgaris does not set seed after sparse flowering, which makes seedling progenies unavailable. A low-cost propagation trial was conducted to explore the clonal propagation techniques for the species with two types of small branch cuttings, nodal leafy cuttings and tip cuttings. The cuttings, after treating with 0, 0.1%, 0.4%, and 0.8% IBA solutions, were kept in non-mist propagator to let them to root for assessing the rooting ability. The cuttings were rooted in four weeks and were allowed to grow in the polybags for 10 months under nursery condition to assess their steckling capacity. The study reveals that both types of branch cuttings are able to develop roots, shoots, to survive and to form rhizome under the nursery condition. Rooting ability of the cuttings was significantly enhanced by the application of rooting hormone - IBA. The highest rooting percentage in nodal leafy cuttings and the tip cuttings (56.67% and 51.0%, respectively) were observed in 0.8% IBA treatment, followed by 0.4% IBA and the lowest (34.3% and 30.0%, respectively) was in control. The highest number of root developed per cutting (9.77 and 8.33 in nodal leafy cuttings and the tip cuttings, respectively) was also obtained from the cuttings treated with 0.8% IBA solution, followed 0.4% IBA treatment and the lowest (3.1 and 2.1, respectively) was in the cuttings without treatment. However, the length of the longest root varied significantly neither with the cutting types nor the concentrations of IBA solution. Survival percentage of the stecklings in nursery condition was significantly enhanced by IBA. 展开更多
关键词 Bambusa vulgaris leafy branch cuttings non-mist propagator rooting ability steckling capacity
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Vegetative propagation of Holarrhena pubescens,a wild tropical medicinal plant:effect of indole-3-butyric acid (IBA) on stem cuttings 被引量:1
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作者 Tarit Kumar BAUL Mohammad MEZBAHUDDIN +1 位作者 Mohammad Mosharraf HOSSAIN Mohammed MOHIUDDIN 《Forestry Studies in China》 CAS 2010年第4期228-235,共8页
The present study investigated the rooting ability and growth performance of juvenile single-node leafy stem cuttings of Holarrhena pubescens, collected from two mature mother trees preserved in the hill forests of Ch... The present study investigated the rooting ability and growth performance of juvenile single-node leafy stem cuttings of Holarrhena pubescens, collected from two mature mother trees preserved in the hill forests of Chittagong District, Bangladesh. The rooting ability of cuttings was studied with 0, 0.1%, 0.2% and 0.4% indole-3-butyric acid (IBA) treatments. The better rooting response was observed with 0.1% IBA, but was insignificant compared to other treatments. The mean number of roots and length of the longest root of cuttings in different treatments showed no significant difference. After transfer to the polythene bags from a nonmist propagator, rooted cuttings treated with 0.4% IBA demonstrated the highest (50.00± 0.78%) survival capacity. Regarding initial growth of established rooted cuttings (stecklings) over a 90 d period, the increment of stem length of stecklings under T2 (10 g Urea, 20 g TSP, 10 g MOP dissolved in 2 L water) and leaf area expansion of stecklings under T1 (10 g Urea, 20 g TSP, 10 g MOP dissolved in 1 L water) was significantly higher (p 〈 0.05) compared with that under TO (no fertilizer). The increment of collar diameter and root biomass production varied insignificantly among different fertilizer concentrations, although stecklings under T2 showed the better performance. The results suggest that rooting juvenile single-node leafy stem cuttings can be an effective mean of regenerating H. pubescens. The application of 0.1% IBA or without IBA is recommended for rooting juvenile leafy stem cuttings. Application of fertilizer appears necessary for subsequent growth of stecklings in polythene bags. 展开更多
关键词 IBA non-mist propagator ROOTING stem cutting stecklings
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改性细水雾灭油池火有效性研究 被引量:4
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作者 贾海林 李第辉 李小然 《安全与环境学报》 CAS CSCD 北大核心 2018年第6期2172-2176,共5页
纯水细水雾熄灭油类火灾初期出现的短暂温度陡升情况,可能会造成油池火灾喷溅进而影响其灭火安全性的问题,遴选了一种烷基酚与环氧乙烷缩合物的非离子液作为细水雾添加剂对其进行改性。通过分析改性细水雾特征参数,利用仿真灭火试验平... 纯水细水雾熄灭油类火灾初期出现的短暂温度陡升情况,可能会造成油池火灾喷溅进而影响其灭火安全性的问题,遴选了一种烷基酚与环氧乙烷缩合物的非离子液作为细水雾添加剂对其进行改性。通过分析改性细水雾特征参数,利用仿真灭火试验平台对不同质量分数的改性细水雾熄灭煤油火进行了试验研究。结果表明,改性后细水雾表面张力降低,比表面积增大。随细水雾中非离子液质量分数增大,灭火时间缩短,火焰温度急剧下降,其灭火效率优于纯水细水雾,当非离子液质量分数为5%时,其灭火效率是纯水细水雾的12.16倍,并且温降速率较纯水细水雾的温降速率提高了2.67倍。改性细水雾熄灭煤油火时没有出现类似纯水细水雾作用下的温度陡升及火焰团现象。原因是:改性后细水雾的雾动量减小,对火焰和周围空气的扰动作用减弱,其穿透火焰区到达燃料表面;由于非离子液的增溶和乳化作用,水分子包裹着油料分子,从而衰减了燃料喷溅现象和表面温度。 展开更多
关键词 安全工程 非离子液细水雾 仿真灭火空间 表面张力 温度陡升 灭火有效性
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Clonal propagation of guava (Psidium guajava Linn.) by stem cutting from mature stockplants
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作者 A.T.M. Abdullah M.A. Hossain M.K. Bhuiyan 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期301-304,共4页
The study describes the scope of clonal propagation of guava (Psidium guajava Linn.) by stem cutting collected from mature stockplants. Cuttings were treated with 0, 0.2%, 0.4% and 0.8% IBA solution and rooted in the ... The study describes the scope of clonal propagation of guava (Psidium guajava Linn.) by stem cutting collected from mature stockplants. Cuttings were treated with 0, 0.2%, 0.4% and 0.8% IBA solution and rooted in the non-mist propagator. Rooted cuttings were allowed to grow in the polybags filled with soil and cow-dung mixed in the ratio of 3: 1 (by volume) for three months to assess the steckling capacity and initial growth performance. The study reveals that the species is amenable for clonal propagation by mature stem cutting. The highest rooting percentage (60%) was observed in the cuttings treated with 0.4% IBA solution followed by 0.2% IBA and the lowest was in controlled cuttings. The maximum number of primary root (32.7) was developed in the cuttings treated with 0.8% IBA solution followed by 0.4% IBA and the lowest was in the cuttings without IBA treatment. The highest survival percentage (70.9) was observed in the cuttings rooted with 0.4% IBA treatment and the lowest (58.3) was in the cuttings without any treatment. However, there was no significant variation in height growth of cutlings due to IBA treatments in rooting. 展开更多
关键词 Psidium guajava Linn. non-mist propagator Stockplants Stem cutting Rooting ability Stecklings
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Effect of Leafy and Leafless Greenwood, Softwood and Hardwood Cuttings Success of <i>Garcinia kola</i>(Heckel)
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作者 Jonas Patrick Dao Kouakou Laurent Kouakou +4 位作者 Camille Kouakou Mamadou Cherif Mahamadi Hamed Ouedraogo Kouame Kevin Koffi Irié Arsène Zoro Bi 《Agricultural Sciences》 2020年第10期897-911,共15页
<em>Garcinia kola</em> Heckel, called “petit cola” in C<span style="white-space:nowrap;">&#244;</span>te d’Ivoire and “bitter kola” in Nigeria, is a Non-Timber Forest Product... <em>Garcinia kola</em> Heckel, called “petit cola” in C<span style="white-space:nowrap;">&#244;</span>te d’Ivoire and “bitter kola” in Nigeria, is a Non-Timber Forest Product of great socioeconomic importance. Unfortunately, this species is threatened due to overexploitation and deforestation. This study tested the effect of leaf area on stem cuttings to regenerate vegetatively in a non-mist poly-propagator without using exogenous hormones. Three stem cuttings types: greenwood, softwood and hardwood (12 - 15 cm in length) were collected from 24-month years old seedlings. The two top leaves of each cutting type were conserved at different leaf area: 0 cm<sup>2</sup>, 28.25 cm<sup>2</sup>, 56.5 cm<sup>2</sup>, 84.75 cm<sup>2</sup> and 113 cm<sup>2</sup> (entire leaf area). Observations were made on rooting, sprouting and leafing abilities of cuttings depending to treatments applied. Results showed that all cutting types have presented good ability to shooting and rooting. Cuttings with 113 cm<sup>2</sup> leaf areas presented the best rooting (94.44% ± 2.42%) and shouting (95.55% ± 2.42%) percentage and longest primary root length (12.03 ± 0.50 cm). Hardwood, softwood and greenwood cuttings with 113 cm<sup>2</sup> leaf area had the best rooting percentage (96.66% ± 3.33%, 96.66% ± 5.77% and 90.00% ± 5.77% respectively). The longest primary root length (13.50 ± 0.97 cm) was observed to greenwood cuttings with 113 cm<sup>2</sup> leaf area. Regenerated plants in the forest presented well survival percentage (96.66%). This study shows that it is possible to regenerate entire plants by cuttings without using external hormones in non-mist poly-propagator. 展开更多
关键词 Garcinia kola Heckel Leaf Area non-mist Poly-Propagator Stem Cuttings Vegetative Propagation
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遥感图像去云雾噪声的实现 被引量:6
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作者 石文轩 吴敏渊 邓德祥 《光学精密工程》 EI CAS CSCD 北大核心 2010年第1期266-272,共7页
为了去除相机拍摄的遥感图像中的云雾,提出了一种新的非局域均值算法来处理遥感图像序列中的云雾噪声。首先,根据遥感图像在云雾阴影下的梯度值的性质,得出了在云雾阴影下图像灰度值偏低而梯度值却变化不大的结论,从而在权重值的计算中... 为了去除相机拍摄的遥感图像中的云雾,提出了一种新的非局域均值算法来处理遥感图像序列中的云雾噪声。首先,根据遥感图像在云雾阴影下的梯度值的性质,得出了在云雾阴影下图像灰度值偏低而梯度值却变化不大的结论,从而在权重值的计算中耦合了梯度值信息。然后,利用序列图像的帧间冗余信息来计算新的权重值。最后,用新的权重值对图像进行恢复。用UltraCamD相机对在我国新疆地区和山西地区上空拍摄的两组遥感图像序列进行的实验表明:与传统的图像恢复算法相比,用提出的方法恢复图像可获得更好的图像质量;与原始图像相比,恢复后图像的峰值信噪比提高了9dB以上。实验结果表明,该算法可以在不知道云层运动方向和相机运动方向以及噪声模型的情况下有效地对薄云雾覆盖的遥感图像进行恢复。 展开更多
关键词 非局域均值 梯度特征 图像序列 图像去噪 云雾
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非分散红外检测空气中油雾方法的探讨 被引量:3
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作者 黄金勇 陈巧 何莲 《环境科技》 2017年第4期65-67,共3页
建立了非分散红外法测定空气中油雾的分析方法。选用四氯乙烯作为萃取剂,油雾质量浓度在10~50 mg/L范围内有良好的线性关系,相关系数r=0.999 5,检出限为2.015 mg/L。采集的6个平行样品的相对标准偏差为0.78;6个加标样品的回收率范围为93... 建立了非分散红外法测定空气中油雾的分析方法。选用四氯乙烯作为萃取剂,油雾质量浓度在10~50 mg/L范围内有良好的线性关系,相关系数r=0.999 5,检出限为2.015 mg/L。采集的6个平行样品的相对标准偏差为0.78;6个加标样品的回收率范围为93.1%~101%。实验证明其方法定量结果准确、回收率高、精密度良好、干扰小,与其他方法相比具有简便快捷、绿色环保等优势。 展开更多
关键词 环境污染 油雾 非分散红外法
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基于空间反射镜的点阵结构非均匀尺寸优化设计 被引量:5
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作者 张牧尧 苏云 王超 《航天返回与遥感》 CSCD 北大核心 2021年第2期123-129,共7页
针对空间反射镜的高轻量化率的工作条件和工作需求,将点阵结构引入到反射镜结构设计,并基于移动阈值切面法(MIST)优化设计了非均匀点阵结构。文章以小口径190mm铝合金反射镜作为研究对象,基于MIST法将点阵杆件进行了非均匀尺寸优化。首... 针对空间反射镜的高轻量化率的工作条件和工作需求,将点阵结构引入到反射镜结构设计,并基于移动阈值切面法(MIST)优化设计了非均匀点阵结构。文章以小口径190mm铝合金反射镜作为研究对象,基于MIST法将点阵杆件进行了非均匀尺寸优化。首先选择点阵单胞,对于实体设计空间进行点阵单胞的填充,实现空间反射镜的均匀点阵设计;然后基于MIST法对于均匀点阵结构进行尺寸优化,将杆件横截面积作为优化对象,得到了轻量化方案。由于反射镜的安装应力会影响面形精度,所以分析了安装应力对于反射镜的面形影响。该方法验证了优化后使用非均匀点阵尺寸优化的反射镜的轻量化率以及面形精度要求均优于传统轻量化形式反射镜,满足设计要求。 展开更多
关键词 空间反射镜 移动阈值切面法 非均匀点阵 轻量化率 拓扑优化 航天遥感
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非离子液细水雾灭火效能与减弱火焰强化现象研究 被引量:1
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作者 贾海林 李小然 李第辉 《河南理工大学学报(自然科学版)》 CAS 北大核心 2018年第6期8-15,共8页
针对细水雾释放初期出现的火焰强化在一定程度上影响细水雾灭火技术的安全适用性问题,基于物理化学、火灾学理论,开展了弱化火焰强化的非离子液添加剂遴选和熄灭油池火的试验。结果表明:非离子液细水雾释放时具有较佳的雾化特征参数,其... 针对细水雾释放初期出现的火焰强化在一定程度上影响细水雾灭火技术的安全适用性问题,基于物理化学、火灾学理论,开展了弱化火焰强化的非离子液添加剂遴选和熄灭油池火的试验。结果表明:非离子液细水雾释放时具有较佳的雾化特征参数,其灭火时间和最高温度增加幅度均随非离子液质量分数的增大而降低;火灾烟气中CO体积分数最大值和维持高CO体积分数的时间均随非离子液质量分数的增大而降低;O_2体积分数降低到最小值和由最小值恢复至常值的恢复速率均随非离子液质量分数的增大而加快。非离子液细水雾具有弱化火焰强化的作用,且扑灭油池火的能力优于纯水细水雾,通过分析,获得了非离子液细水雾弱化火焰强化的机理。其主要灭火机理:一是非离子液细水雾喷出后形成的悬浮气泡和水泡沫具有阻隔热辐射、隔断O_2供应和隔离可燃物与O_2接触的作用;二是非离子液具有较低的HLB值,且细水雾因高温作用,与水分子以氢键链接的醚基断裂,增强了捕捉煤油分子和销毁链式反应中H·和OH·的能力。上述研究成果,对于细水雾灭火技术在油品火灾的高效、安全扑救方面具有重要意义。 展开更多
关键词 火焰强化 非离子液细水雾 灭火效能 悬浮气泡
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太钢立式1280mm不锈钢板坯连铸机改造 被引量:1
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作者 王西林 刘光辉 +1 位作者 周亚君 李如同 《重型机械》 2000年第2期39-42,51,共5页
介绍了太钢立式 12 80 mm不锈钢板坯连铸机的成功改造情况 ,改造后的连铸机主要技术性能及所采用的新技术、新设备 :无氧化浇注 ,结晶器冷却水合理分配 ,气 -水雾化二冷技术 。
关键词 火焰切割 斜出坯 无氧化浇注 板坯连铸机
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桂花非试管快繁技术研究
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作者 张丽 艾薇 王友如 《生物资源》 CAS 2020年第2期243-247,共5页
以一年生丹桂枝条为材料,探索桂花非试管快速繁殖最佳条件。用不同浓度吲哚乙酸(IBA)浸泡插条基部,对比不同实验组材料的生根率。实验结果显示,200 mg/L的IBA处理的桂花枝条,在定时控制喷雾条件下,插后55 d的生根率和成苗率达100%。本... 以一年生丹桂枝条为材料,探索桂花非试管快速繁殖最佳条件。用不同浓度吲哚乙酸(IBA)浸泡插条基部,对比不同实验组材料的生根率。实验结果显示,200 mg/L的IBA处理的桂花枝条,在定时控制喷雾条件下,插后55 d的生根率和成苗率达100%。本研究对加快桂花培育速度、对深化桂花快繁技术研究具有重要意义。 展开更多
关键词 桂花 非试管快繁 喷雾 生根
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