Preparation and Evaluation of a Self-Nanoemulsifying Drug Delivery System Loaded with Heparin Phospholipid Complex

A self-nanoemulsifying drug delivery system (SNEDDS) was developed to enhance the absorption of heparin after oral administration, in which heparin was compounded with phospholipids to achieve better fat solubility in the form of heparin-phospholipid (HEP-Pc) complex. HEP-Pc complex was prepared using the solvent evaporation method, which increased the solubility of heparin in n-octanol. The successful preparation of HEP-Pc complex was confirmed by differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, NMR, and SEM. A heparin lipid microemulsion (HEP-LM) was prepared by high-pressure homogenization and characterized. HEP-LM can enhance the absorption of heparin after oral administration, significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT) in mice, and reduce fibrinogen (FIB) content. All these outcomes indicate that HEP-LM has great potential as an oral heparin formulation.     

耦合膜分离的新型CO2低温捕集系统性能优化

CO₂捕集作为温室气体排放控制的有效手段已成为重要研究课题。作为新兴捕集技术之一，低温CO₂捕集因产品纯度高、无附加污染等优势受到关注。然而，该技术能耗和捕集率对于气体中CO₂浓度十分敏感，对于高CO₂浓度气体可获得较高的CO₂捕集率和较低能耗水平。基于此，本文提出了耦合膜分离的新型CO₂低温捕集系统，通过膜材料选择渗透性实现待捕集气体CO₂浓度主动调控，并在最优浓度下进行CO₂低温捕集。首先基于不同传统低温捕集系统特点，对比分析了不同耦合系统模式，从而确定了最优耦合系统结构。针对最优耦合系统进行了运行参数优化，并分别基于实现系统捕集能耗最低与捕集率最高的目标，获得了膜渗透侧CO₂浓度与进气CO₂浓度间的关系式，为该耦合系统中膜组件选型提供指导。研究表明，本文提出的耦合系统捕集能耗为1.92MJ/kgCO₂，相比于传统单一低温系统捕集能耗可降低16.5%。     

肠靶向海藻酸钙基微胶囊的制备及控释性能研究

利用毛细管共挤出技术结合静电吸附和仿生硅化的方法，制备了海藻酸钙-壳聚糖/精蛋白/二氧化硅(ACPSi)复合微胶囊。ACPSi复合微胶囊的平均粒径约3.18 mm，单分散性好，囊壁最外层的二氧化硅层可抑制其在肠液pH环境中的溶胀，增强囊的机械稳定性。将羟丙甲基纤维素邻苯二甲酸酯(HPMCP)肠溶微球作为释药“微阀门”，嵌入囊壁可以更好地控制微胶囊的释药行为。以吲哚美辛为模型药物，当药物浓度为22.5 mg/ml时，ACPSi载药微胶囊在pH 2.5模拟胃液中3 h时累计释药率仅为0.33%，而转移至pH 6.8模拟肠液中19 h时累计释药率为77.78%；囊壁嵌入HPMCP微球后，22 h时累计释药率可提高约4%。因此，该复合微胶囊具有良好的肠靶向作用和控释特性，作为口服肠靶向缓控释制剂具有良好的应用前景。     

双季戊四醇在3种混合溶剂中的固-液相平衡

采用动态平衡法，在293.15～332.80 K、常压下，测定了双季戊四醇(DPE)在水+(甲醇、乙醇、异丙醇)三种混合溶剂中的溶解度数据。结果表明：DPE在不同质量分数的水+(甲醇、乙醇、异丙醇)混合溶剂中的溶解度随体系温度升高而增大；同一温度下，其在所选取溶剂体系中的溶解度随着甲醇、乙醇或异丙醇质量分数的增大而先增大后减小。λh方程、两参数方程与Apelblat方程均能够对所测定的溶解度数据进行较好的关联；通过修正的van’t Hoff方程计算得到DPE在所选取溶剂体系中Δ_sol H ⁰、Δ_sol S ⁰和Δ_sol G ⁰均大于零，表明DPE在所选取溶剂体系中的溶解过程为吸热、熵增的非自发过程。     

Fractional order battery modelling methodologies for electric vehicle applications: Recent advances and perspectives

Science China Technological Sciences - Accurate modelling of lithium ion batteries is crucial for battery management in electric vehicles. Recent studies have revealed the fractional order nature...     

河南省灵宝市董家埝银矿原生晕特征及地质意义

董家埝银矿是豫西小秦岭矿集区南成矿带目前发现的唯一大型矿床。为了矿床深部勘查工作的顺利进行,了解有用元素在垂向上的变化规律,选用原生晕地球化学方法,通过典型矿床剖面的原生晕特征研究,实现对深部矿体变化趋势的判断。经计算,确定As、Sb、Ag、Au、Cu、Pb、Zn、Co和Mo等9种元素可作为指示元素,其中As和Sb为前缘晕指示元素,Ag、Au、Cu、Pb和Zn为近矿晕指示元素,Co和Mo为尾晕指示元素。分带指数和浓集指数2种方法计算得出的元素在分带序列上的位置总体趋势一致。用分带指数法确定的主矿体自上而下的原生晕轴向分带序列为Co-Mo-Cu-Au-Sb-Zn-Pb-Ag-As,出现"反分带"现象。结合原生晕地球化学参数变化特征、矿体剥蚀程度研究和理想模型,预测M1-I主矿体向深部仍有较大的延伸。研究成果可以为区域同类型矿化地质体深部的趋势判断和决策提供参考。     

iRGD-reinforced,photo-transformable nanoclusters toward cooperative enhancement of intratumoral penetration and antitumor efficacy

Nano Research - Insufficient intratumoral penetration greatly hurdles the anticancer performance of nanomedicine. To realize highly efficient tumor penetration in a precisely and spatiotemporally...     

用于厚屏蔽小探测器的蒙特卡罗模拟减方差方法研究

反应堆屏蔽计算中经常出现厚屏蔽、小探测器问题，常规蒙特卡罗方法难以有效解决。基于自动重要抽样（AIS）方法，本文提出了小探测器自动重要抽样(SDAIS)方法，并针对小探测器问题，优化了AIS方法的虚粒子赌分裂算法。该方法在自主开发的蒙特卡罗屏蔽程序MCShield上进行了实现。使用NUREG/CR-6115 PWR基准题验证该方法的正确性和计算效率。结果表明，SDAIS方法可有效地解决厚屏蔽小探测器问题，相比AIS方法及传统的重要性方法，计算效率提升1~2个量级。     

Digital Microfluidics for Manipulation and Analysis of a Single Cell

The basic structural and functional unit of a living organism is a single cell. To understand the variability and to improve the biomedical requirement of a single cell, its analysis has become a key technique in biological and biomedical research. With a physical boundary of microchannels and microstructures, single cells are efficiently captured and analyzed, whereas electric forces sort and position single cells. Various microfluidic techniques have been exploited to manipulate single cells through hydrodynamic and electric forces. Digital microfluidics (DMF), the manipulation of individual droplets holding minute reagents and cells of interest by electric forces, has received more attention recently. Because of ease of fabrication, compactness and prospective automation, DMF has become a powerful approach for biological application. We review recent developments of various microfluidic chips for analysis of a single cell and for efficient genetic screening. In addition, perspectives to develop analysis of single cells based on DMF and emerging functionality with high throughput are discussed.