饱和土体固结压缩和蠕变的热力学本构理论及模型分析

岩土热力学模型（thermodynamic soil model,TSM）是基于颗粒固体的非平衡态热力学理论,建立的一种崭新的描述岩土力学问题的统一理论模型。该模型引入“颗粒熵运动”和“弹性弛豫”,对土体颗粒层次的耗散机制进行了合理地考虑,这些使得模型能够更深入描述土体的变形和能量耗散机理,从而能够在统一理论框架中描述岩土体复杂多变的物理力学行为。基于该理论模型,研究了饱和土体的固结压缩和蠕变问题,分析了加载速率、应力/应变路径和非单调荷载等因素的影响规律。模拟结果表明：模型具有描述复杂条件下的饱和土体的固结压缩和蠕变特性的能力,具有较高的理论和工程应用价值。     

米糠固脂与棕榈硬脂混合应用于起酥油的研究

米糠固脂是米糠油冬化或分提获得的副产物。以3种具有不同固体脂肪含量(SFC)曲线的米糠固脂(RBS1、RBS2及RBS3)、棕榈硬脂(PS)为原料,按照米糠固脂与棕榈硬脂质量比40∶60进行二元混合制备起酥油,并以市售起酥油为参考,对混合体系的SFC、晶型、脂肪酸组成、微量营养素含量进行了分析。结果表明:由不同米糠固脂组成的二元混合体系差异不大,且与市售起酥油具有相似的SFC曲线;其棕榈酸、亚油酸含量较市售起酥油高,硬脂酸含量较市售起酥油低;体系表现为β'晶型;此外,二元混合体系中含有丰富的谷维素、植物甾醇,可丰富起酥油的营养特性。     

Site selection in waste management by the VIKOR method using linguistic assessment

Site selection is an important issue in municipal solid waste (MSW) management. Selection of the appropriate solid waste site is an extensive evaluation process that requires consideration of multiple alternative solutions and evaluation criteria. In reality, it is easier for decision makers to express their judgments on the alternatives by using linguistic terms, and there usually exists uncertain and incomplete assessment information. Moreover, decision makers may have different risk attitudes in the siting process because of their different backgrounds and personalities. Therefore, an attitudinal-based interval 2-tuple linguistic VIKOR (ITL-VIKOR) method is proposed in this paper to select the best disposal site for MSW. The feasibility and practicability of the proposed method are further demonstrated through an example of refuse-derived fuel (RDF) combustion plant location. Results show that the new approach is more suitable and effective to handle the MSW site selection problems by considering the decision maker's attitudinal character and incorporating the uncertain and incomplete assessment information.     

捆绑式望远镜中间块对镜筒指向误差的影响分析

运用SolidWorks软件的静态分析模块,将捆绑式望远镜中间块的动态分析转化为0°~90°范围内,均匀分布的18个位置的静态分析。中间块每转动5°,对其上基面的镜筒连接圈的位移变化进行数据采集一次,计算出各镜筒之间的夹角变化值并进行对比,最终得到镜筒之间的最大指向误差。此方法为解决同类问题提供了参考价值。     

Particulate matter chemical component concentrations and sources in settings of household solid fuel use

Particulate matter (PM) air pollution derives from combustion and non‐combustion sources and consists of various chemical species that may differentially impact human health and climate. Previous reviews of PM chemical component concentrations and sources focus on high‐income urban settings, which likely differ from the low‐ and middle‐income settings where solid fuel (ie, coal, biomass) is commonly burned for cooking and heating. We aimed to summarize the concentrations of PM chemical components and their contributing sources in settings where solid fuel is burned. We searched the literature for studies that reported PM component concentrations from homes, personal exposures, and direct stove emissions under uncontrolled, real‐world conditions. We calculated weighted mean daily concentrations for select PM components and compared sources of PM determined by source apportionment. Our search criteria yielded 48 studies conducted in 12 countries. Weighted mean daily cooking area concentrations of elemental carbon, organic carbon, and benzo(a)pyrene were 18.8 μg m^?3, 74.0 μg m^?3, and 155 ng m^?3, respectively. Solid fuel combustion explained 29%‐48% of principal component/factor analysis variance and 41%‐87% of PM mass determined by positive matrix factorization. Multiple indoor and outdoor sources impacted PM concentrations and composition in these settings, including solid fuel burning, mobile emissions, dust, and solid waste burning.     

Folate-mediated solid–liquid lipid nanoparticles for paclitaxel-coated poly(ethylene glycol)

Background: As a promising anticancer drug, severe side-effects of current clinical formulations for paclitaxel have restricted its use, developing a better technical-economical formulation for paclitaxel delivery is needed. Method: In this study, the compound of folate-poly(ethylene glycol) (PEG)-phosphatidylethanolamine was synthesized and characterized with Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The solid-liquid lipid nanoparticle (SLLN) for paclitaxel modified with folate and poly(ethylene glycol) (folate-PEG-SLLN) was prepared and characterized. Morphology of folate-PEG-SLLN was examined by transmission electron microscopy. The particle size and zeta potential were performed by Zetapals. Encapsulation efficiency was analyzed by HPLC. The in vitro drug release of paclitaxel was investigated via membrane dialysis. The in vivo pharmacokinetics was measured with male Sprague-Dawley rats. Treatment efficiency was investigated with the mouse with sarcoma180 ascites tumor. Results: Paclitaxel loaded on the newly designed binary SLLN showed a longer and sustained in vitro releasing property. More importantly, S180 tumor-bearing mice treated with paclitaxel-loaded SLLN exhibited higher tumor inhibition rate, comparing with animals administered with paclitaxel injection alone (45.3% and 37.3%, respectively). Conclusion: The newly developed paclitaxel delivery system may have improved in vivo antitumor activity. The results demonstrated a great interest to use folate-mediated SLLN as a prospective drug delivery system for paclitaxel.     

Physicochemical stability,pharmacokinetic, and biodistribution evaluation of paclitaxel solid dispersion prepared using supercritical antisolvent process

Aim: To investigate the physicochemical stability, pharmacokinetics (PK), and biodistribution of paclitaxel (PTX) from paclitaxel solid dispersion (PSD) prepared by supercritical antisolvent (SAS) process.

Methods: Physicochemical stability was performed in accelerated (40°C 70?±?5% RH) and stress (60°C) storage conditions for a period of 6 months and 4 weeks, respectively. PK and biodistribution studies were performed in rats following i.v. administration of PTX equivalent to 6 and 12?mg/kg formulations.

Results: Physical stability of PSD showed excellent stability with no recrystallization of the amorphous form. Chemical stability of PSD in terms of % PTX remaining was 98.2?±?0.6% at 6 months and 97.9?±?0.3% at 4 weeks of accelerated and stress conditions, respectively. The PK study showed a nonlinear increase in AUC with increasing dose, that is, 100% increase in dose (from 6 to 12?mg/kg) resulted in 405.90% increase in AUC. Unlike PK study, the organ distribution study of PTX from PSD showed linear relationship with dose escalation. The order of organ distribution of PTX from highest to lowest for both PSD and Taxol^® was liver>kidney>lung>brain.

Conclusions: This study demonstrated excellent physicochemical stability with insight information on the PK and biodistribution of PTX from PSD prepared by SAS process.     

固体超强酸催化剂在制备合成酯中的应用

固体超强酸催化剂可以降低酯化温度，提高酯化效率。主要介绍了固体超强酸催化剂在制备合成酯中的应用。