超增溶自组装制备纳米氧化铝渣油加氢催化剂载体

采用超增溶胶团自组装体原位合成纳米微粒方法合成了氧化铝渣油加氢催化剂载体,并通过扫描电镜、吸附脱附BET法和热重分析表征其结构。结果表明,制备的超增溶纳米自组装氧化铝载体性能稳定,分布均匀,具有较大的孔径、比表面积和孔容,强度高,堆积密度小,符合纳米粒子特性。     

木薯酒精渣同步糖化发酵制乙醇的工艺研究

研究了利用木薯酒精厂废渣为原料发酵生产乙醇的方法,结果表明:经过简单的机械粉碎后,通过同步糖化发酵生产乙醇是可行的。发酵条件为:木薯酒精渣经粉碎后取粒径小于0.85mm的部分,初始料水比1∶8,纤维素酶添加量为每克木薯渣(干重)30FPU,发酵过程中在24h内分批将剩余木薯渣加入至总料水比达到1∶2.5,利用5L发酵罐进行同步糖化发酵,发酵液中乙醇质量浓度达到52g/L,木薯酒精渣到乙醇的收率达到13%。纤维素酶的添加量对发酵效果影响显著,当达到每克木薯渣(干重)50FPU时,发酵液中乙醇质量浓度可达65g/L,乙醇收率达到16%。     

微波等离子体法合成重油残渣基定向纳米碳薄膜

以重油残渣为原料,采用微波等离子法制备了一种结构新颖的定向纳米碳薄膜材料。经场发射扫描电子显微镜、高分辨透射电子显微镜分析,结果表明：产物纯度较高,外观呈条状麦穗形,各条状物平行排列形成定向阵列,最大宽度约为65nm,长度可达900nm左右;麦穗的主干表层和穗片晶化程度较好,层与层之间清晰可见,中心部位为非晶态,可能是产物经历了由外向内的生长过程,重油残渣中的重金属Ni、Fe等对其生长起了一定的催化作用。     

Development and in vivo response of hydroxyapatite/whitlockite from chicken bones as bone substitute using a chitosan membrane for guided bone regeneration

Biomaterials that meet the requirements to stimulate bone tissue formation play a vital role in orthopedics and dentistry. In this work, chitosan and a biphasic, non-cytotoxic material hydroxyapatite/whitlockite were obtained from natural sources, which are available as organic waste. The osteogenic activity was assessed using a rabbit model animal with a chitosan barrier membrane in combination with a bone-filling graft substitute composed of hydroxyapatite/whitlockite. FT-IR results showed the typical absorption bands of the chitosan and hydroxyapatite. Moreover, the X-ray diffraction pattern revealed a typical hexagonal phase of hydroxyapatite and rhombohedral structures related to whitlockite. Masson's trichrome stain showed an early formation of extracellular matrix mineralized, in accord with the surface morphology of a cortical mature bond observed by Scanning Electron Microscopy. The immunocytochemistry results showed a significant increase of positive immunoreactive cells to osteonectin in the treated defects in comparison with the control defects 6 and 8 weeks postoperatively. Overall, the results confirm that the use of this low-cost and versatile biomaterial as a barrier membrane and a bone substitute graft are useful for bone tissue engineering.     

Fabrication and characterization of bone china using synthetic bone powder as raw materials

The synthetic bone powder was studied as a raw materials for bone china, completely replacing natural bone ash raw materials. The physical and thermal properties of samples obtained by the two bone powders were tested and comparatively studied. Performance tests included pyroplastic deformation, flexural strength, bulk density, sintering shrinkage, water absorption, transmittance, thermal expansion coefficient and the thermal shock resistance. The phase composition and morphology were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results indicated that using synthetic bone powder could shorten the preparation time, reduce the sintering temperature and result in high-quality bone china. The pyroplastic deformation decreased from 9.14% to 7.92%, the three-point flexural strength increased from 123 MPa to 191 MPa, the light transmittance (at a 2-mm thickness) increased from 6.7% to 11.2%, the thermal expansion coefficient decreased from 8.24×10⁻⁶ °C⁻¹ to 7.69×10⁻⁶ °C⁻¹, and the thermal shock resistance increased from 140 °C to 180 °C. A continuous interface layer without cracks was produced by using the synthetic bone powder.     

枯草芽孢杆菌发酵甘草渣产2,3-丁二醇和乙偶姻的初步研究

甘草渣是甘草提取完活性成分后的剩余物，富含木质纤维素。以甘草渣为研究对象，以2种稀碱（Na2CO3水溶液和NaOH水溶液）以及稀碱（Na2CO3水溶液或NaOH水溶液）和醋酸乙醇胺离子液体混合液为溶剂对甘草渣进行预处理，研究不同碱浓度和预处理温度对甘草渣组成及酶解效果的影响。结果表明，质量分数2%的NaOH水溶液在固液比（w/v）1:10（即每克甘草渣加入10毫升溶剂）、100 ℃条件下预处理甘草渣1.5 h，木质素去除率达54.1%、纤维素回收率为77.2%；样品酶解24 h，葡萄糖得率可达53.5%，较预处理前甘草渣（10.6%）提高了4.0倍。最后，对预处理后的甘草渣进行高固酶解，在固液比3:10、酶用量45 FPU/g生物质条件下酶解72 h，葡萄糖产量达到86.2 g/L、木糖18.9 g/L。以此酶解液为碳源进行发酵，96 h后发酵液中2,3-丁二醇和乙偶姻总产量为43.9 g/L，还原糖转化率为0.42 g/g；与对照组相比，酶解液更有利于菌体生长，生产强度提高，但转化率略低。     

Determination of the mineralization of nitrogen from composted chicken manure as affected by temperature

Incubations at 5, 10 or 20°C of composted chicken manure in a sand, clay or loam soil consistently released nitrogen. A statistical model fitted to the data confirmed that the temperature dependence followed an Arrhenius pattern. The data were used to test the hypothesis that composted manure behaves more like native soil organic matter than fresh residues and this idea is illustrated with the use of a computer simulation model. Extrapolation of the model results in several climates suggests that about 40% of the organic N in composted chicken manure becomes available to crops during the first year and 6–12% during each subsequent year.     

城市污泥厌氧发酵残渣热解制备生物炭及其氮磷吸附研究

以污泥发酵前后的残渣热解制备生物炭,考察发酵前后污泥生物炭的物理性能及其对氨氮、总磷的吸附能力。实验结果表明污泥发酵有利于生物炭孔隙结构的发展,污泥发酵后制备的生物炭(FSBC)比表面积、孔体积均高于未发酵污泥制备的生物炭(SBC)。吸附实验结果表明,对于磷酸盐的吸附,3种材料吸附能力大小为 FSBC > SBC > CAC,对于氨氮的吸附,吸附能力顺序为CAC > FSBC > SBC,污泥发酵后制备的生物炭对氨氮和总磷的吸附能力较未发酵污泥生物炭明显增强。对于实际废水中氮、磷的吸附,其去除率顺序均为CAC > FSBC > SBC,其中CAC和FSBC对总磷的去除率分别为31%和27%,对氨氮的去除率则分别为7%和4%。FSBC与CAC对总磷和氨氮的去除率相差不大。FSBC作为污泥资源化得到的低成本吸附剂,有广阔的研究前景。     

Preparation of mesoporous silica nanoparticles with controlled pore size,particle diameter,morphology, and structure by two-step process of chlorosilane residue

In this study, mesoporous silica nanoparticles (MSNs) were successfully prepared in two steps using chlorosilane residue. First, chlorosilane residue was subjected to alcoholysis with n-propanol to synthesize tetrapropoxysilane (TPOS), followed by the synthesis of MSNs using TPOS as silicon source. Alcoholysis experiment was designed and optimized using orthogonal experimental method. In addition, effects of four factors (i.e., molar ratio of n-propanol to chlorosilane residue; feed rate of n-propanol; reaction temperature; and molar ratio of n-hexane to chlorosilane residue) on the yield of TPOS were investigated. The optimum alcoholysis conditions were determined. Yield of TPOS was 56% under the optimum alcoholysis conditions. Results obtained from single factor analysis of variance revealed that molar ratio of n-propanol to chlorosilane residue was the most significant factor affecting TPOS yield. Next, a series of spherical MSNs with dendritic structure and irregular mesoporous/microporous silica nanoparticles with non-dendritic structure were successfully synthesized via precise regulation of various experimental parameters in emulsion systems. In this regard, the adjustment of n-hexanol/1,3,5-triisopropylbenzene (TIPB) molar ratio or n-octane/n-hexanol/TIPB molar ratio was found to be effective for achieving controllable regulation of morphology (spherical or irregular); structure (dendritic or non-dendritic); pore size (mesoporous (4.6–9.2?nm) or microporous (1.6–1.7?nm)); and particle diameter (60–134?nm) of silica nanoparticles. However, the adjustment of n-octane/TIPB molar ratio marginally affected spherical morphology, dendritic structure, and pore size (4.0–4.6?nm) of synthesized MSNs, with considerable effect on particle diameter (61–151?nm). In addition, as-synthesized MSNs exhibited large specific surface area (708–857?m²/g) and large pore volume (1.5–3.6 cm³/g).     

负载型杂多酸催化剂催化乙醇脱水制乙烯

合成了负载型杂多酸催化剂-磷钼酸/5A分子筛,并用红外光谱对其进行了分析。探讨了杂多酸浸渍浓度,浸渍时间,焙烧温度及焙烧时间对乙醇脱水制乙烯收率的影响,实验表明:杂多酸浸渍浓度0.002moL.L-1,浸渍回流时间24h,焙烧温度400℃,焙烧时间4h,催化剂活性最高,乙烯收率可达98.9%以上。     

响应面优化Al3+配位改性天然高分子骨胶黏合材料的制备

采用Al³⁺配位改性天然高分子骨胶黏合材料,应用响应面优化法优化尿素用量、十二烷基硫酸钠(SDS)用量和配位反应温度3个因素对天然高分子骨胶黏合材料黏度和凝固点的影响。根据Box-Behnken实验设计原理,使用Design-Expert (V8.0.6.1)软件对实验进行设计与分析,以黏度和凝固点为响应量,建立响应量的回归模型,分析各因素的显著性与交互作用。结果表明最佳工艺条件为:m_尿素= 0.78g,m_SDS =0.5g,T_配位=60.56℃;响应量预测值为:凝固点4.2℃,黏度4.575Pa·s。     

Preparation of carbon microcoils by catalytic decomposition of acetylene using nickel foam as both catalyst and substrate

Carbon microcoils (CMCs) were prepared by catalytic pyrolysis of acetylene containing a small amount of thiophene as a promoter at 973-1073 K using nickel foam catalyst which was also used as a substrate, with the CMC yield of about 62% relative to the introduced carbon source. The morphology of the product was observed by scanning electron microscopy (SEM). The morphology of the nickel foam was changed during synthesis, and the sulfur promoter and growth temperature were two important factors influencing the growth of CMCs.     

Extraction of protein from skim natural rubber latex using PEG as a surfactant via low speed centrifugation and continuous flow

Protein extractions from skim natural rubber latex using 3 %w/v polyethylene glycol (PEG6000) via both low speed centrifugation and continuous flow were investigated. In centrifugal extraction, when the speed was 1000 rpm, the extractable protein (EP) content in serum increased with processing time from 5 to 30 min and when the time was fixed at 5 min, EP content increased with centrifugal speed. In addition, further washing deproteinized chips with 2 %w/v SDS solution could remove proteins with efficiencies corresponding to the efficiencies of protein removals in latex phase, implying the role of PEG in protein reduction in both steps. In continuous flow extraction, EP content increased with increasing Reynolds number or increasing mean residence time of the flow to a maximum and then dropped. The efficiencies of the centrifugal extraction and continuous flow extraction were 55.2 and 33.7%, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39900.     

Synthesis of biodiesel from Scenedesmus sp. by microwave and ultrasound assisted in situ transesterification using tungstated zirconia as a solid acid catalyst

Oleaginous Scenedesmus sp. was cultivated phototrophically in an open pond for biofuels production. The culture was harvested and subsequently dewatered and dried. The chemical properties of the Scenedesmus sp. lipids were determined as per standard ASTM methods. Biodiesel was synthesized by in situ transesterification from dried biomass using microwave and sonication techniques with tungstated zirconia (WO₃/ZrO₂) as a solid acid catalyst. In situ transesterification allowed minimizing the requirement of solvents by merging the two steps (i.e. extraction of lipid and conversion to biodiesel) to a single step. The use of a solid catalyst effectively reduces the purification cost of biodiesel due to ease of separation and potential for reuse. The conversion of Scenedesmus sp. lipids to biodiesel was determined by GC. Box–Behnken design was used for optimization of the variables to optimize the biodiesel yield and conversion. The efficiency of the two processes was compared.     

Preparation and properties of porous Al2O3-based ceramics by gel casting using MgO as a gelling and consolidating agent

Low-cost and environment-friendly MgO was used as a new gelling and consolidating agent to fabricate porous Al₂O₃-based ceramics via a gel casting routine. Effects of 800°C calcined additions of MgO (.5, 1.0, 1.5, and 2.0 wt%, respectively) on open porosity (OP), pore size distribution, gas flux, and microstructure of the porous ceramics were investigated deliberately. The experimental results showed that 800°C calcined MgO exhibits excellent gelling and consolidating performance at 80°C, mainly owing to the hydration reaction between MgO and H₂O and thus results in high-quality porous Al₂O₃-based ceramics without deformation and cracking. The Al₂O₃–water suspensions with different MgO additions have good flowability at room temperature. Moreover, water absorption, open porosity, and gas flux of the as-prepared porous ceramics increase remarkably with rising of MgO addition. Furthermore, MgO addition significantly suppresses the abnormal growth of Al₂O₃ grains, and thus the microstructure of the porous Al₂O₃-based ceramics becomes more uniform. This technique of gel casting using MgO as a new gelling and consolidating agent offers an alternative routine for a large-scale production of porous ceramics.     

Study of the interaction of poly(acrylic acid) and poly(acrylic acid‐poly acrylamide) complex with bone powders and hydroxyapatite by using TGA and DSC

The thermo gravimetric analysis (TGA) and differential scanning calorimetric analysis (DSC) were used to study the thermal degradation of poly(acrylic acid) PAA and poly(acrylamide) PAAm as well as the compound obtained from their interactions. The examination of the thermal curves revealed that the characteristics of the curves of the compound resulting from the cooperative interactions are different from those of the constituent polymers. The differences in the characteristics of the thermal curves were attributed to the formation of an interpolymer complex resulting from the interaction of PAA with PAAm at low pH value. These two thermal techniques were also used to investigate the thermal behavior of the compounds obtained from the interaction of PAA and (PAA‐PAAm) mixture with bone powders (BP) and hydroxyapatite (HA). It was found that the TGA, DTG, and DSC curves do not show the peak of formation and degradation of PAA anhydride which provided strong evidence for the consumption of PAA in the reaction between the polymer and BP. The interaction between PAA and the thermally treated BPs and HA was investigated. Moreover the interaction between the mixture of PAA and PAAm at different pH values and the BPs and HA was discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007