不同形态水分对煤自燃过程微观作用机制研究

制备不同外在水分和原始赋存水分含量的煤体,通过模拟煤自燃升温氧化过程得到不同温度下的氧化煤样;利用原位傅里叶红外变换光谱仪测定不同氧化煤样中活性官能团的含量,研究形态水分对煤自燃过程微观官能团生成和转化的影响;利用氮吸附仪表征不同氧化煤样中比表面积大小,研究形态水分对煤自燃过程微观孔结构变化的影响;同时结合官能团与比表面积的变化规律,探讨形态水分对煤自燃过程的微观作用机制。形态水分对煤自燃过程的作用机制随着煤自燃状态发展而发生变化,表现出阶段性特征。外来水分含量和原始赋存水分都会促进酚、醇类羟基及含羧基类化合物的生成。外来水分和原始赋存水分的含量对煤自燃过程中微观比表面积、脂肪族C−H组分、含羟基化合物以及含羰基类化合物的生成和转化影响具有差异性;水分形态对微观比表面积和脂肪族C−H组分含量的变化影响具有差异性,而对含羟基化合物以及羧基化合物的生成和转化具有相似性。

沙土孔隙内水分形态及分布

通过CCD结合显微镜实验观察研究了沙土孔隙内水分分布形态。通过研究分析认为,除了传统上认为沙土中水分有吸附水、结合水和容积水等形态之外,相对粗糙的骨架表面还存在表面毛细水。低含湿率时,孔隙内水分形态有吸附水、结合水、表面毛细水和液桥(容积水);高含湿率时,孔隙中的水分并不是按孔隙均匀分布,而是出现大团水体中夹杂气团。对于气团中的孔隙,水分形态仍然有吸附水、结合水、表面毛细水和液桥。

花岗岩残积土颗粒及水分形态三维微观结构

采用高分辨率X射线计算机断层扫描技术(X-rayμ-CT)对花岗岩残积土三维微观结构进行重构并在以下方面取得新进展:(1)通过在试样液相中添加显影物质(CsCl),成功获取土中水分形态及空间分布;(2)利用X射线在不同物质中的衰减率差异,进一步区分固体颗粒中高岭石与石英并确定各自空间分布;(3)通过三维重构图像,对颗粒空间接触关系进行初步概化与分类,同时对X射线计算机断层扫描技术在非饱和土力学中的进一步应用做了前瞻。这些初步探索将有助于对土体三维真实结构的全面认识,促进计算机断层扫描技术在岩土/地质工程领域的新开拓。

基于低场核磁和差示量热扫描的面条面团水分状态研究

为了解低水分面条面团中水分的存在状态,明确真空度及和面时间对水分状态的影响,该研究以3个小麦品种(济麦20、宁春4号、济麦22)磨制的面粉为材料,采用真空和面制作低水分面条面团(含水率35%),采用低场核磁共振技术(LF-NMR,low-field nuclear magnetic resonance)和差示量热扫描(DSC,differential scanning calorimetry)2种技术,测定不同真空度(0、0.06、0.09 MPa)和搅拌时间(4、8、12 min)下面团中水分的形态和分布,并进一步分析2种技术测定水分形态结果的相关性。结果表明,在低水分面条面团中,水分主要以弱结合水形态存在。不同品种的小麦粉面团的水分形态及分布存在差异,强筋小麦粉(济麦20)制作面团的水分自由度较低。真空和面(0.06 MPa)可以促进水分与面筋蛋白的相互作用,降低面团中水分子流动性,促进水分结构化;而非真空或过高真空度均会导致面团中水分自由度增加。济麦20、济麦22小麦粉和面时间为8 min时,面团水分流动性较低;而宁春4号小麦粉面团在4 min时,水分自由度较低;继续搅拌,深层结合水减少、弱结合水增多。LF-NMR和DSC测得面团水分状态的结果具有一致性。LF-NMR测得的弱结合水峰面积百分比与DSC测得的可冻结水百分比具有相同的变化趋势(r=0.695),且深层结合水峰面积百分比与非冻结水百分比具有相同的变化趋势(r=0.564)。研究结果为认识制面过程中水分的作用,优化和面工艺和调整产品特性提供参考。

昭通褐煤气力输送临界水分含量研究

研究昭通褐煤水分含量对其气力输送的影响，获得了其输送临界水分含量，并从煤粉流动性出发，对临界水分进行了初步解释，得到了初步判别标准。进一步从褐煤水分赋存形态出发，对临界水分问题进行了探讨。结果表明：昭通褐煤全水分约29％时，输送表观气速出现大幅度增大，全水分约30％时无法正常输送，判断其输送临界水分为29％～30％。煤粉流动性测量可为临界水分判别提供初步参考标准。在临界水分附近，煤粉流动性发生区域转变，流动性变差。粒间水是影响煤粉流动和输送的主要水分因素，粒内水对输送的影响很小。虽然褐煤全水分较高，但大量水分以粒内水形式存在，粒间水含量较少。昭通褐煤输送临界水分附近，粒间水含率约为6％，粒间水占粒间空隙体积的比率约为7％。

初始pH对餐厨垃圾生物干化脱水效率的影响

目前餐厨垃圾生物干化脱水效率较低,处理周期长,难以满足后端资源化利用的需求。以生石灰调控不同初始pH分别为5、6、7的3个处理,记为CK、T1、T2,探究不同初始pH下餐厨垃圾生物干化反应的脱水效率,与反应过程中的水组分行为转化规律。结果表明,生物干化反应中,T1与T2的有效积温为512.0、509.1℃,高于CK处理的454.2℃,CK、T1与T2的脱水率分别为74.2%、78.2%、76.0%,说明T1处理脱水效果最好。不同初始pH调控影响有机质降解,CK、T1与T2处理的有机质的降解率分别为26.9%、30.0%、29.4%,但处理间生物干化效率无显著差异。生物干化过程中,游离水是主要的水分赋存形态,随着反应的进行,多层水(multilayer water,MW)与毛细水(capillary water,CW)不断向滞化水(entrapped water,EW)转化,且CW与MW对水分去除贡献较大,不同初始pH通过影响MW、CW的水分去除而影响水分转化与去除。本研究可为餐厨垃圾生物干化工业规模应用的初始pH调控提供参考。

固化污泥压缩特性研究

固化技术是污泥进行填埋处置常用的处理技术之一,固化污泥的压缩参数是进行填埋场库容计算和稳定性评价的重要指标。选用水泥作为固化材料,开展了不同材料添加量和不同养护时间条件下固化污泥的压缩特性研究,并从固化污泥水分形态和转化角度对压缩性变化机理进行了探讨。结果表明,即使水泥添加量达到30%,固化污泥的压缩指数也高达0.71,是一种高压缩性的土。水泥的添加量在10%~20%时,固化污泥压缩指数降低显著,但是超过20%以后,压缩指数变化趋于稳定。其原因主要在于污泥中的水分具有较高的结合势能,过多的水泥并不能获得更多的自由水发生水化反应。固化污泥的压缩指数随着养护时间的增加而降低,当达到14 d时趋于稳定,但60 d以后压缩指数又出现降低趋势,其原因主要是微生物逐步分解污泥结合水中的碳氢化合物,有机质含量下降,导致压缩指数降低。

污泥固化土强度特性研究

为明确污泥固化处理后的强度变化特征,并从水分转化角度揭示其变化机理,对不同水泥添加量和不同养护龄期条件下污泥固化土的强度特性进行了室内试验研究。结果表明:(1)污泥固化土的无侧限抗压强度与水泥添加量呈线性正相关,固化系数k随着养护龄期的增加而增大。0~14 d,k由0.807 9增大到1.251 8,增长幅度较大,为54.94%;14~28 d,k由1.251 8增大到1.488 7,增长幅度明显减小,为18.92%。(2)无侧限抗压强度与养护龄期之间呈现良好的正相关性,二者拟合的相关系数在0.969 8~0.999 7之间。(3)水泥主要与污泥中结合势能较低的自由水发生水化反应,随着水泥添加量的增加,自由水百分量降低明显,下降幅度达到47.7%,结合水百分量降低缓慢,下降幅度仅9%;且水化反应在14 d内基本完成,14 d内水化反应消耗的自由水含量约为28 d内的80%。研究成果可为污泥固化土这种特殊性质土体的基本力学性质研究提供基础参数,为实际固化施工工艺的选择提供了参考。

生物组织冻融特性的初步实验研究

以几种典型生物材料为对象,对生物组织冻融过程中的传递现象和界面特性进行可视化实验观测,着重考察冰晶生长及其界面的推进情况,应用微CT技术研究生物组织冻融前后内部结构变化,探讨不同生物材料和冷冻条件下冻融特性的差异。在实验观测的基础上,定性分析了生物组织中水分存在形态对冻融过程特性的影响。

Morphological Phylogeny of the Water Snake Subfamily Homalopsinae (Serpent: Colubridae)

The morphological phylogeny of the water snake subfamily Homalopsinae, containing 10 genera, of which seven are monotypic, was not reported up until now. Here fourteen morphological characters were selected for the cladistic analysis. Using software Hennig 86, two phylogenetic trees were inferred and the results showed that the subfamily Homalopsinae was divided into two groups. Compared with the molecular phylonenetic tree of Voris et al （2002）, the genera Gerarda and Fordonia are sister groups in both studies; both studies also yielded the same monophyletic lineage, which contained three genera （Cerberus ＋ Erpeton ＋ Homalopsis ）. However, the position of the genus Cantoria is distinctly different with the study of Voris et a1（2002）.

疏浚淤泥有机质含量及其对固化淤泥强度的影响

水环境治理过程中采用底泥疏浚的方法会产生大量疏浚淤泥.传统的处理处置方法难以处置大量淤泥,通过化学改良对其进行固化处理后资源化利用是一个切实可行的方法.但是,疏浚淤泥中含有一定量的有机质,有机质含量对淤泥固化效果的影响不可忽略.对27种不同来源疏浚淤泥进行了有机质含量调查与测定,并选取其中7种进行了不同有机质成分含量的测定与分析,明确有机质中对固化淤泥强度产生影响的有机质成分后,采用添加相应有机质成分的方式,研究有机质含量对淤泥固化效果的影响并分析其机理,最后针对大连湾疏浚淤泥,提出其富里酸含量对固化淤泥强度影响阈值为5.89%.

市政污泥的水热反应减量化及水分赋存形态研究

针对市政污泥处理处置受难脱除的高水分含量制约的现状,基于水热技术可越过高能耗的脱水工艺实现高效减量化的效果,开展了水热反应中市政污泥减量化及水分赋存形态研究,从效果和机理角度明确了水热技术处理市政污泥可实现高效减量化。结果表明:水热反应温度达到500℃时,市政污泥减量率达到87.60%,有机质的去除率达到62.7%;市政污泥中赋存的水分形态在水热升温过程经过细胞胞内水分释放、固相残留含水率降低、固相产物脱水性能改善等三个阶段;水热技术在控制过氧比为0.2时具备最优的处理效果和经济优势。

利用液态DME对市政污水厂脱水污泥深度脱水的研究

探讨了液态二甲醚(DME)对脱水污泥进行深度脱水时浸泡时间和添加量对脱水效果的影响,并对后续的资源化利用进行了探讨。结果表明,液态DME可以应用于脱水污泥的深度脱水,且污泥的脱水率随反应时间和DME添加量的增大逐渐增大,最大可以达到90%以上,此时,含水率可以降至30%。其深度脱水的原理主要体现在反应前期主要是自由水的脱除,反应后期以结合水脱除为主,结合水脱除率可以达到80%以上。由于水分的大量脱除,脱水后污泥的低位热值明显上升,有利于后续的资源化利用。

Morphological and genetic comparison of two strains of a Prorocentrum species isolated from Zhejiang coastal water of China and Masan Bay of Korea

In this paper, we examined the detailed morphology of two strains of Prorocentrum isolated from the coastal waters of Zhejiang (Wenling area), China, and Masan Bay of Korea. A taxonomic comparison was made among strains on the basis of morphological and molecular data. The cellular dimensions of the Chinese Wenling strain (LAMB090508) and Korean strain (PDKS0206) were similar and the cells of both strains were of asymmetric and elongated shape. The posterior end of most cells was rounded. Megacytic zones of aged cells were broader with dense tiny knobs. The roundish nucleus was located in the posterior part of the cell. A few irregular shaped chloroplasts were distributed within the cell. The nucleotide similarity of the two strains, determined from the 5.8S rDNA-ITS sequences, was 99.83%. The comparative results of morphology and molecular analysis suggest that both strains isolated from China and Korea were the identical species, Prorocentrum donghaiense Lu.

Controlling dispersion and morphology of MoS2 nanospheres by hydrothermal method using SiO2 as template

Monodispersed MoS_2 nanospheres were successfully synthesized by using SiO_2 as hard template. The size and morphology of the MoS_2 nanospheres could be finely controlled by the content of SiO_2 and sulfur precursors. Furthermore, higher surface area of monodispersed MoS_2 nanospheres exhibited high reaction rate for hydrodesulfurization(HDS) of dibenzenethiophene(DBT).

Application of otolith shape analysis for stock discrimination and species identification of five goby species(Perciformes: Gobiidae) in the northern Chinese coastal waters

We tested the use of otolith shape analysis to discriminate between species and stocks of five goby species( Ctenotrypauchen chinensis, Odontamblyopus lacepedii, Amblychaeturichthys hexanema, Chaeturichthys stigmatias, and Acanthogobius hasta) found in northern Chinese coastal waters. The five species were well differentiated with high overall classification success using shape indices(83.7%), elliptic Fourier coefficients(98.6%), or the combination of both methods(94.9%). However, shape analysis alone was only moderately successful at discriminating among the four stocks(Liaodong Bay, LD; Bohai Bay, BH; Huanghe(Yellow) River estuary HRE, and Jiaozhou Bay, JZ stocks) of A. hasta(50%–54%) and C. stigmatias(65.7%–75.8%). For these two species, shape analysis was moderately successful at discriminating the HRE or JZ stocks from other stocks, but failed to effectively identify the LD and BH stocks. A large number of otoliths were misclassified between the HRE and JZ stocks, which are geographically well separated. The classification success for stock discrimination was higher using elliptic Fourier coefficients alone(70.2%) or in combination with shape indices(75.8%) than using only shape indices(65.7%) in C. stigmatias whereas there was little difference among the three methods for A. hasta. Our results supported the common belief that otolith shape analysis is generally more effective for interspecific identification than intraspecific discrimination. Moreover, compared with shape indices analysis, Fourier analysis improves classification success during inter- and intra-species discrimination by otolith shape analysis, although this did not necessarily always occur in all fish species.

Simulation of Morphological Development of Soil Cracks in Yuanmou Dry-hot Valley Region, Southwest China

Soil cracking is an important process influencing water and solutes transport in the Yuanmou Dry-hot Valley region of Southwest China. Studying the morphological development of soil cracks helps to further reveal the close relationship between the soil cracking process and water movement in such semi-arid regions. Here we report regular changes on surface morphology of soil cracks with decreasing water in four different soils (Typ-Ustic Ferrisols,Ver-Ustic Ferrisols,Tru-Ustic Vertisols and Typ-Ustic Vertisols) through simulation experiments. Our results indicate the following: 1) Different soils ultimately have different development degrees of soil cracks,according to their various values of crack area density. Soil cracks in Typ-Ustic Ferrisols can only develop to the feeble degree,while those in the other three soils are capable of developing into the intensive degree,and even into the extremely intensive degree. 2) Soil crack complexity,as expressed by the value of the area-weighted mean of crack fractal dimension (AWMFRAC),is found to continuously decrease as a whole through the whole cracking process in all the studied soils. 3) Soil crack connectivity shows a uniform trend in the studied soils,that is to say,connectivity gradually increases with soil crack development.

Responses of Carex lasiocarpa Morphorlogical Characters to Water Regimes at Different Growth Stages

[Objective] The morphological characters of C.lasiocarpa were studied to find its morphological responses to different water regimes and growth stretagies through different water experiences.[Method] A seeding transplanting experiment with controlled water levels was set up,and the water level was changed at the middle of the season to compare water influence at the seeding stage and later growing period.C.lasiocarpa height,leaf length,leaf number,rhizome and adventitious roots length were measured at certain time througth the growing season.[Result] Results at the thriving season indicated that C.lasiocarpa height and leaf length in the experiment were similar to that in the field,but leaf number was higher under-5 cm water level and dry-wet alternate conditions than that in the field.At later growth period,height and leaf length under constant flooding(15cm) was significantly higher than that under other culture conditions,and also that of the field investigation;while the leaf number had a trend as-5 cm water level treatment>constant flooding>dry-wet alternate>field investigation.The height and leaf length were sensitive to seeding stage water effects,and leaf number sensitive to later influences.[Conclusion] Changes of water regimes in the growing season disturbed the growth of C.lasiocarpa,could accelerate or suspend its wilt,and modified the length of life history.

Morphometric Comparison of White Tambaqui （Piaractus brachypomus） in Lentic and Lotic Environments

The purpose of this paper is looking for associations between environmental factors and morphological parameters in tambaqui （Piaractus brachypomus） individuals to differentiate this species in lentic environments （lake） and lotic （river）. In this, regard studied 30 specimens, 15 from lentic environment （lake） and 15 from lotic （river）. Also, on right profile of these 25 morphometric variables were measured. On data matrix a PCA （principal components analysis） based on morphometric correlations matrix, which was defined in the new morphologic space of these specimens （3 principal components） which explain 73.23% of variability. Fish projection in first two principal components showed a morphological differentiation between two environments （lentic and lotic）, with variables as, horizontal eye diameter, length maxilla, suggesting greater response of these fish in lotic environment by their adaptation to light conditions, predators threat and food distribution. Finally, in lotic environment these fish have thinner caudal peduncle, indicating greater plasticity, namely stylized fish.

Effects of Gradual Water Deficit Stress on Phenological and Morphological Traits in Chickpea （Cicer arietinum L.）

The aims of this study were to investigate the effect of gradual water deficit stress on some phonological and morphological traits and grain yield of desi and kabuli chickpea cultivars. This study was carried out in 2007 and 2008, to evaluate responses of three chickpea cultivars （Hashem and Arman from kabuli and Pirooz from desi type） under well watering （I1： 70mm evaporation from class A pan）, gradual water deficit （12 and 13： 70→90→ 110→130 and 70→100→130mm evaporation from class A pan, respectively） and severe water stress （14： 130mm evaporation from class A pan）. Result showed that days to flowering and plant height were decreased, as water limitation increased. This reduction was significant under gradual water stress （I2 and I3） and Severe water deficit （I4）, compared with control （I1）. There were no significant differences in grain filling period and grain yield among I~, I2 and I3 irrigation treatments. No significant differences in days to physiologic maturity and number of sub branches were recorded among irrigation treatments. Interactions of year×cultivar for days to physiologic maturity, grain filling period and grain yield （P≤0.01） and for days to flowering and plant height （P≤0.05） were significant. The superiority of Arman in producing comparatively greater grain yield could be attributed to higher grain filling period of this cultivar in both years.