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元宝枫产业的研究现状与展望 总被引：1，自引：0，他引：1
本文总结了元宝枫在种质资源、育种研究、栽培实用技术以及生产加工等环节的研究现状,同时结合产业实际的发展现状,提出产业研究中育种、栽培和加工等环节中仍存在优良品种少、育种方法单一、栽培技术停滞、加工技术落后等问题,并针对以上问题给出相应解决建议。 相似文献
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孚尔默成立于在1909年,最早经营用于锯齿刀片修整的磨齿机,目前产品包含应用于木工加工行业和金属加工行业锯片和工具的磨削和电火花机器。在该集团从单一的木材加工进入到金属加工业的发展历程中,逐步发展了刃磨、测量等业务,并在电火花和刃磨技术、激光加工等新型技术的导入上不遗余力。 相似文献
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节能环保型木材加工设备的开发 总被引：1，自引：0，他引：1
花军 《林业机械与木工设备》2009,37(12):4-8
从可持续发展的战略高度出发,采用现代设计方法、应用先进制造技术和工艺,围绕节能环保型木材加工设备的开发途径,在木材加工设备切削机理、结构改进和新型刀具开发,在新产品创新设计、高新技术应用和推动节能环保型木材加工设备的发展等诸多方面进行了深入分析。 相似文献
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木材加工中四面刨的选择 总被引：1，自引：0，他引：1
对木材加工中常用的铣削加工工具——四面刨从分类、加工工艺范围、加工工艺特点等方面作了详细介绍，建议在生产中根据实际情况具体分析，灵活掌握，多选用中型偏小和小型四面刨，以最大限度地发挥设备效用。 相似文献
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以美姑县为例,分析了少数民族地区核桃发展中存在的管理粗放、提早采摘、加工不当等主要问题,提出了加强对种植户病虫害防治知识和采摘、加工技术培训,探讨了虫害防治、适时采摘、正确加工等措施,确保核桃增产增收. 相似文献
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通过对黑龙江省森林资源、木材资源和省内木材加工企业情况进行调研,从原材料供应成本、产业结构、产业科技含量和产业融合度等四方面对黑龙江省木材加工企业存在问题进行深入分析,并从优化产业结构、打造产业集群、建设服务平台、加大政策投入、利用区位优势、强化科技创新等方向,对黑龙江省木材加工企业产业转型升级提出合理化的策略与建议,旨在提高木材加工企业发展质量,助力龙江木材加工产业振兴。 相似文献
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This study clarified the origin of Al in spring water and stream water by analyzing the size distribution of Al of ground
water, spring water, stream water, and soil extracts obtained by batch and column experiments using samples from a suburban
secondary forest on granite bedrock in Aichi Prefecture. The high concentration of dissolved Al (Al0.45; fraction through 0.45-μm filter) in water samples obtained from this study site was divided into completely dissolved and
small colloidal forms (<0.20 μm; Al0.20) and large colloidal forms (0.20–0.45 μm). More than 50% of dissolved Al (Al0.45) in spring water existed in large colloidal form. By comparing the size distribution and concentration of various elements
including Al in the samples from soil batch and column experiments, we suggest that the high concentration of Al in spring
water is caused by the release of Al from surface soils when ground water emerges as spring water. 相似文献
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用淀粉-聚丙烯酸型及聚丙烯酸型两种高吸水性树脂对地表水和水中几种离子的吸附进行了研究。结果表明：高吸水性树脂具有阳离子交换树脂的性质，对阳离子有较强的吸附能力，对阴离子的吸附能力较弱；吸附能力因吸水剂种类、离子性质及浓度而异。 相似文献
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Two-year-old, container-grown red spruce (Picea rubens Sarg.) seedlings from a New Hampshire seed source were exposed to 10 or 11 drying cycles in which the seedlings were not watered until their midday (1400 h) xylem water potentials averaged -1.57 MPa. Control seedlings were kept well watered to maintain midday water potentials of about -0.73 MPa. After the final drying cycle, the water-stressed seedlings were rehydrated and osmotic potentials were determined by pressure-volume analysis. Gas exchange at ambient CO(2) concentration (338 ppm) and at an elevated CO(2) concentration (838 ppm) was measured on both groups of plants as they slowly dried down. No osmotic adjustment or photosynthetic acclimation occurred as a result of the water-stress treatment and both groups of seedlings maintained photosynthesis to water potentials as low as -3.0 MPa. Twenty-four hours after rehydration, the water-stressed seedlings had photosynthetic rates as high as the control seedlings. Estimated stomatal limitation to photosynthesis was approximately 30% down to water potentials of -1.4 MPa, but increased steadily as water potentials decreased further. At ambient CO(2) concentrations (338 ppm) and water potentials averaging -2.45 MPa, photosynthetic rates of water-stressed seedlings were 15% those of well-watered seedlings, whereas when the same water-stressed seedlings were measured in the presence of an elevated concentration of CO(2) (838 ppm) their photosynthetic rates were 73% those of well-watered seedlings measured at an ambient CO(2) concentration (338 ppm). 相似文献
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粉煤灰具有较高的孔隙率和比表面积,能吸附去除水中多种污染物。以粉煤灰为主要原料制成球形复合滤料,可以解决粉煤灰粉末难以有效利用的问题。利用粉煤灰基质滤料分别对水中高浓度和低浓度Cr（Ⅵ）进行静态吸附实验,探究吸附时间、滤料量、初始浓度对Cr（Ⅵ）吸附效果的影响。结果表明：该粉煤灰基质滤料对水中高浓度（10~30.00mg/L）的Cr（Ⅵ）具有较强的吸附能力,滤料投加量对Cr（Ⅵ）去除效果影响较大,时间对Cr（Ⅵ）的去除影响较小。在滤料用量为700g/L,控制温度为35℃,初始浓度为30mg/L,转速为200 r/m in的条件下振荡60m in,Cr（Ⅵ）去除率可达到85.25%以上。 相似文献
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以葛根为原料,以葛根素为主要评价指标,研究了葛根中各主要活性成分的含量、葛根黄酮的制备、葛根黄酮饮品的稳定性及极端条件的破坏性、葛根黄酮饮品口感及感官指标、葛根黄酮饮品生产工艺等。结果表明:与泰国葛根、粉葛等相比,湘葛一号葛根中葛根素等活性成分含量明显较高。不同浓度乙醇提取葛根总黄酮,以65%乙醇提取效果最好。湘葛一号天然葛根饮品的制备过程中,低浓度(21.6 mg/500 mL)、中浓度(216 mg/500 mL)饮品在不同温度条件下的葛根黄酮均无明显变化,含量稳定;高浓度(360 mg/500 mL)饮品葛根黄酮含量均有不同程度减少,稳定性稍差;中、高浓度饮品葛根黄酮高温易氧化变色,低温易沉淀析出,故低浓度饮品稳定性最佳。在各浓度葛根饮品中,每500 mL含葛根素100 mg及以下的葛根饮品颜色透明清亮;每500 mL含葛根素2.16 mg等低浓度的饮品与纯净水无明显口感差异,21.6 mg级别的饮品口感微苦,并有一种清凉感,适合饮用。 相似文献
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指出了高浓度难降解有机废水对环境危害很大，此类废水采用常规技术一般无法处理或者处理效果差且运行费用高。超临界水氧化（SCWO）是一种新兴的，很有前景的处理高浓度难降解有机废水的环保技术，具有很多特色和优势。介绍了处理高浓度、难降解、小流量有机废水的超临界水氧化处理中试装置，采用该装置对造纸黑液、制药废水、化工废水和军工废水等不同种类的高浓度难降解有机废水进行了处理。最大处理量为12．5L/d ，化学需氧量（COD）的去除率＞99％，处理后的排放水质可以达到国家规定的排放标准。 相似文献
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Soil CO2 levels reflect CO2 production and transport in soil and provide valuable information about soil CO2 dynamics. However, extracting information from soil CO2 profiles is often difficult because of the complexity of these profiles. In this study, we constructed a simple numerical
model that simulated soil CO2 dynamics and performed sensitivity analyses for CO2 production rates, soil water content and temperature, and gas diffusivity at the soil surface to clarify the relationships
among these parameters. Increased soil surface CO2 flux did not always coincide with higher soil CO2 concentrations; increased CO2 production at shallow depths had little effect on soil CO2 concentrations, while the opposite may be true for high levels of soil water content. Higher soil CO2 concentration did not always coincide with greater soil surface CO2 flux; under high soil water conditions, soil surface CO2 flux sometimes decreased despite increased soil CO2 concentration. Increases in soil water content did not always enhance both soil surface CO2 flux and soil CO2 concentration. Under high soil water conditions, increases in soil water content could lower soil surface CO2 flux and increase soil CO2 concentration. Increases in soil temperature resulted in greater soil surface CO2 flux and higher soil CO2 concentration in our simulation (extremely high temperatures were not assumed in this study). Gas diffusivity in very shallow
layers did affect, albeit weakly, soil CO2 concentration. The findings of this study may help direct future observations and aid in the interpretation of their results. 相似文献
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The role of abscisic acid (ABA) in the mediation of stomatal responses to low leaf water potential was examined with intact plants and epidermal strips of Populus trichocarpa Torr. & A. Gray. Clones of this species grown under well-watered conditions maintain a high leaf conductance when the foliage wilts. However, foliar ABA concentration in P. trichocarpa increased manyfold in response to water stress as it did also in P. deltoides Bartr. ex Marsh. and P. trichocarpa x deltoides hybrids. Application of ABA to epidermal strips appeared to cause solute leakage, however stomata of P. trichocarpa remained partially open even when the guard cells were plasmolyzed. Foliar application of ABA induced closure of stomata in young expanding leaves, but not in fully expanded foliage. Ten days after ABA application, stomata on young leaves were open at high water potential but closed at low water potential. These characteristics are discussed with respect to wilty mutants of tomato and potato, which also have stomata unresponsive to leaf wilting. 相似文献
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为了考察壳聚糖用于景观用水除菌的可行性,以郑州市某社区景观用水为对象,通过改变壳聚糖酸溶剂种类、pH值、壳聚糖分子量和浓度等,研究壳聚糖在不同情况下的杀菌效果.结果表明:不同酸溶剂对CTS杀菌作用有较大影响,综合考虑多种因素,最终选用乙酸作为CTS的酸溶剂;pH值为5时,壳聚糖杀菌作用最强;壳聚糖杀菌率随浓度的增大而增大,浓度为1.5 g/L时,杀菌率可达80%以上;分子质量为4.4和740 ku的CTS,杀菌率明显高于其它分子量,曲线出现峰值的时间分别为在5和4 h,原因为随着分子量的变化,CTS杀菌作用方式也随之发生变化,最终确定选用价格低廉的高聚合度CTS(分子质量为740 ku). 相似文献
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模拟降水量变化对毛乌素油蒿幼苗生物生态过程中的影响研究 总被引：10，自引：0，他引：10
毛乌素是中国干旱、半干旱沙区典型沙地，其中水分是最大限制因子，随着未来全球变化，尤其是降水变化进一步激烈，将给这里的陆地生态系统分布格局和生产力带来巨大影响，本文选择毛乌素沙地优势灌木油蒿为研究对象，人控４种降水量梯度来探讨油蒿幼苗的生理生态对降水量的响应。结果表明，不同施水量的油蒿幼苗净水合速率、蒸腾速率、气孔导度、胞间ＣＯ２浓度、叶片温度、光能利用率、水分利用率日变化动态存在明显差异，当少量施水时，幼苗受到明显水分胁迫，故而关闭气孔，降低气孔度和蒸腾速度，以免过多的蒸腾失水。当充分施水时，幼苗叶片气孔开放，提高气孔导率、胞间ＣＯ２浓度和蒸腾速率，降低叶片温度、以此提高光合作用。不同施水的油蒿幼苗表现出不同的生理生态适应策略，幼苗荧光效率随着施水量增大，从机理上解释了幼苗光合作用随着施水量的增加而增长；向后剔除变量分析表明，随着施水量的增加，限制幼苗净光合速度的主要因子逐渐减少。当充人地水时，幼苗主要受到光合有效辐射和叶片温度的限制。当中度施水时，幼苗主要受到蒸腾速率、胞间／大气ＣＯ２浓度差值的限制，不少量施水量时，幼苗主要受到蒸腾速率、气孔导度、胞间／大气ＣＯ２浓度差值、叶片／大气温度差值及其大气温度的限制。 相似文献