北京九龙山林地对降雨的调蓄功能*

对北京九龙山油松林、侧柏林、阴坡灌木林、阳坡灌木林的林冠层、枯落物层及土壤层对降雨的调蓄功能进行了研究，结果表明：四种不同林地的林冠截持率为２２％～３２％，大暴雨下的截持率为７％～１０％；枯落物层的有效调蓄为０．４６～２．４２ｍｍ；５０ｃｍ土层的快速、慢速和变化调蓄量分别为３５～４８ｍｍ；５４～４８ｍｍ，２８～５２ｍｍ；四种林地调蓄功能的顺序从大到小为油松林、阴坡灌木林、阳坡灌木林、侧柏林。     

Impacts of fractal features of soil on moisture infiltration capacity of typical stands in Jinyun mountain of Chongqing city

The soil structure was expressed with fractal dimensions of particle size distribution (PSD), aggregate size distribution (ASD), and soil pore size distribution (SPD). The effect of soil fractal features on soil infiltration velocity and process was studied. The result of the fractal feature shows that fractal dimensions of PSD are obviously greater than those of ASD and SPD, and in different soil genetic horizons, the fractal dimension of ASD has the greatest variability, and shows a downtrend on the top-to-bottom genetic horizon. According to the soil infiltration process curve, the infiltration process was divided into three phases: (1) the initial phase (0–5 min), (2) the transition phase (5–30 min), and (3) the stable phase (30–180 min). In the initial phase of infiltration, the soil structure of soil genetic horizon A was the major influencing factor; in the transition phase of infiltration, the pore distribution of soil horizon AB and soil structure of horizon B were the major influencing factors; in the stable phase of infiltration, the soil structure of horizon C was the major influencing factor to the infiltration velocity. Soil infiltration process is influenced comprehensively by soil PSD, ASD, and SPD. In the overall soil water infiltration, the infiltration in shrub forest land was much faster than that in other land uses, and in the initial infiltration phase, arable land soil infiltration was much faster than that in forest land, and in the stable infiltration phase, the infiltration velocity in forest land was faster than that in arable land. __________ Translated from Journal of Beijing Forestry University, 2006, 28(3): 73–78 [译自: 北京林业大学学报]     

香樟木屑真空热解蒸气催化前后产物对比分析(英文)

在两段式反应器上开展了对香樟木屑真空热解蒸气的在线催化提质研究。对比分析了催化前后各相产物产率和气体组成的变化,以及催化前后液相产物理化特性和化学组成。结果表明,催化后液相产物产率降低,但生物油出现分层,上层为油相,下层为水相。油相的H/C物质的量之比、pH值和高位热值(湿基)分别为1.712、4.93和37.15 MJ/kg;油相中烃类和轻质酚类等目标产物含量明显增加,而酸类、醛类和酮类等具有腐蚀性和不稳定性的化合物含量则显著降低,燃料品质较生物原油有显著提升;水相中仍含有少量腐蚀性和不稳定化合物,但其干基的高位热值达32.98 MJ/kg,除去水分后亦可将其用作替代燃料。热解蒸气中非目标产物在HZSM-5分子筛的活性位点上发生转化反应生成期望化合物,各类反应遵循碳正离子反应机理。     

不同森林-土壤类型在水源林生态系统中的作用

水源林是森林水文学的研究主体和实践区域,丘陵山区开发利用首先要解决水源林布局问题,使之达到生态平衡。文章探讨了不同的森林—土壤类型及其水源涵养能力,阐述了森林—土壤类型在森林生态系统中的基本核心功能,特别是林地土壤内的重力水库容在其中担负着重大的作用,并初步提出了营建和改造水源林的建议。     

DISPERSAL PATTERN OF INJECTATE FOLLOWING CT‐GUIDED PERINEURAL INFILTRATION IN THE CANINE THORACOLUMBAR SPINE: A CADAVER STUDY

An increasing proportion of canine patients are presented with chronic thoracolumbar back pain and without compressive spinal lesions. In humans, spinal perineural infiltrations have been reported to have a favorable effect on pain control. The purpose of this prospective cadaver study was to describe the dispersal pattern of injectate following CT‐guided spinal perineural infiltration in the canine thoracolumbar region. Seven fresh canine cadavers were first scanned using multislice CT and then CT‐guided spinal perineural infiltration was performed at 42 sites from T13/L1 to L6/L7. The injectate for each site was a mixture of new methylene blue and iodinated contrast medium. Immediately following CT‐guided injection, cadavers were frozen, cut, and dissected macro‐ and mesoscopically (using a magnifying glass) to identify anatomic structures that were infiltrated. In the majority of sites (64.3%), complete epidural and hypaxial staining of spinal nerve components (including the spinal ganglion, trunk, and ventral branch) was successfully achieved. However, no (11.9%) or unpredictable staining (9.5%) of nervous tissue occurred in some sites despite careful CT guidance and the application of relatively large volumes of injectate. Optimal results were achieved when the needle tip was positioned periforaminally ventral to the cranial contour of the cranial articular process. Findings from this ex vivo study indicated that CT‐guided spinal perineural infiltration is feasible for testing in the canine thoracolumbar region and that successful nerve tissue infiltration would likely occur in the majority of sites. Future in vivo studies are needed to determine the safety and efficacy of this technique.     

AHP-熵权法结合Box Behnken响应面法优化当归微波真空干燥工艺研究

为探究当归微波真空干燥的最佳工艺参数,以甘肃定西“岷归1号”为试验材料。运用HPLC法测定不同干燥温度、切片厚度、真空度条件下当归中藁本内酯（LA）、阿魏酸（FA）、洋川芎内酯H（SH）、洋川芎内酯I（SI）、绿原酸（CA）、丁烯基苯酞（BA）、抗氧化性（DPPH）、总酚（TPC）、总黄酮（TFC）、多糖（Pc）的含量,利用AHP-熵权法计算各有效活性成分的复合权重和综合评分;以综合评分为响应值,通过Box Behnken响应面法进行优化设计,确定当归微波真空干燥的最佳工艺参数。结果表明：AHP-熵权法计算得出LA、FA、SH、SI、CA、BA、DPPH、TPC、TFC、Pc、RR的Qj值分别为0.159、0.192、0.120、0.288、0.033、0.063、0.059、0.041、0.024、0.013、0.009;Box Behnken响应面法得到的当归微波真空干燥的最优工艺条件为干燥温度50 ℃、切片厚度5 mm、真空度-0.070 MPa,此时综合评分为84.95分;此外,微观电镜结果也表明在此工艺条件下,样品质构热稳定性最好且内部出现均匀规则的蜂窝状孔隙结构。因此AHP-熵权法可用于当归微波真空干燥工艺中多目标的优化。     

抽排厕所废物原位发酵回用可行性研究：杭桥村案例

为适应农村居民对现代化生活的追求、顺应可持续发展的趋势,本研究结合我国农村实情提出以“抽吸式-源分离-就地就近资源化”为技术路线的现代资源化模式作为农村家庭粪尿处置与利用的解决方案,选取一自然聚落,建设服务于20户居民的示范工程开展可行性研究。方案采用组合式多级厌氧发酵制肥工艺对单独收集的抽排厕所废物进行无害化处理,就地就近回用于附近农田,考察抽排厕所废物性质,对制肥设施进行定期监测,并于运行32个月后破拆清扫、取样分析。结果显示：设施未出现堵塞、满溢及渗漏现象,污泥积累不超过设施总有效高度的20%且充分稳定,具有维护简单、清扫周期长的特点;设施出液及底泥均未检出活寄生虫卵,粪大肠菌值>10^-4,符合《粪便无害化卫生要求》（GB 7959—2012）中的卫生标准;设施出液及底泥的总养分含量分别为0.18%和0.43%,有机质含量分别为0.05%和2.65%,每年产生的出液及污泥共计可取代氮肥（N）161.19 kg、磷肥（P₂O₅）9.67 kg、钾肥（K₂O）42.11 kg。现代资源化模式的成功运用不仅可以提高居民生活水平,还能满足可持续发展要求,降低家庭废物处理成本的同时,实现资源就地回用,具有较高的工程应用和推广价值。     

咸淡轮灌和生物炭对滨海盐渍土水盐运移特征的影响

为利用滨海地区微咸水改良盐渍土,进行了不同咸淡水轮灌(淡淡、淡咸、咸淡、咸咸)和施用生物炭(0、15、30 t/hm^2)的室内入渗试验,探讨了咸淡轮灌和生物炭施用下滨海盐渍土水盐运移过程。结果表明:滨海盐渍土水分运动主要受初始入渗水质的影响,先咸后淡的轮灌方式更有利于土壤水分入渗,入渗速率增加了8.2%~46.9%,并小幅提高了土壤含水率;生物炭可促进咸淡轮灌下的水分运移,增加了相同时间内的湿润锋距离、累计入渗量、入渗速率及入渗后的土壤含水率,添加量为15 t/hm^2时入渗增益最佳,入渗速率提高了3.5%~22.0%;淡咸和咸淡处理的土壤含盐量均低于咸咸处理,脱盐率和脱盐区深度系数更高,咸淡处理可增加脱盐率,而淡咸处理可提高脱盐区深度系数;生物炭有利于咸淡轮灌下的土壤盐分淋洗,脱盐率和脱盐区深度系数分别提高了9.1%~15.0%和1.1%~7.5%,并增加了Ca^2+和Mg^2+含量,促进Na+淋洗,进而降低了微咸水利用风险,但在30 t/hm^2时盐分淋洗效果有所减弱。研究表明,添加15 t/hm^2生物炭配合微咸水-淡水轮灌能够改善滨海盐渍土的入渗特性、持水能力和盐分分布,可为该区盐渍土和微咸水开发利用提供参考。     

大黄鱼仔、稚、幼鱼发育阶段的脂肪酸组成及其变化

为了探讨真空冷冻干燥过程参数对冻干时间和能耗的影响，以墨西哥湾扇贝为研究对象，设计二次正交回归组合试验方案，采用SAS统计软件对试验数据进行回归分析，建立了真空冷冻干燥时间和能耗的二次多元回归模型，并对二次多元回归模型进行了F检验；利用降维法定性地分析了物料厚度、干燥室压强和加热板温度3个主要过程参数对真空冷冻干燥时间和能耗的影响。结果表明，物料厚度、干燥室压强和加热板温度对冻干时间和能耗影响显著，并呈二次函数规律变化，在本试验条件下影响的主次因素依次为：物料厚度、干燥室压强、加热板温度。对单位厚度冻干时间进行岭嵴分析，给出了在本试验因素取值范围内的冻干过程优化参数：物料厚度为9mm；干燥室压强为50Pa；加热板温度为39℃，优化的物料单位厚度冻干时间为0．41h。     

河套灌区畦田内不同位置土壤入渗特性及影响因素分析

为明确河套灌区畦田田块不同位置土壤的入渗特性,通过野外试验和室内检测对试验区田块不同位置土壤理化性质和入渗过程进行分析,并基于土壤入渗模型对试验区田块不同位置的土壤入渗过程进行拟合,同时探讨影响土壤入渗过程的影响因素.研究结果表明:试验区田块内不同位置土壤理化性质及入渗特性具有一定差异性且不同位置土壤入渗特性与土壤理化...