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A polysaccharide, chitosan, was chemically modified to form a polyelectrolyte complex membrane with calcium alginate beads. A key factor in membrane for mation was found to be the viscosity average molecular weight (M v) of the chitosan. While unmodified chitosan (Mv = 12.1 x 105) formed thin and weak microcapsule membranes, when the Mv of the chitosan was reduced to 2.4 x 105, the polymer exhibited optimum membrane forming characteristics in terms of capsule strength and flexibility. The degree of deacetylation of chi tosan varied from 94.3% for the unmodified polymer to 93.2% for chitosan of Mv = 1.6 × 105. A substitution reaction sequence was developed in an attempt to modify the pendant amine of the practical grade polysaccharide. Reactive groups were coupled to the chitosan main chain following a two-step process; activation with a bromoacetyl halide and termination with a diamine [(NH2 (CH2)nNH2)] or methyl containing amine compound. Initial studies indicated that thin capsule membranes formed regardless of application of reaction se quence, distance of reactive groups from the main chain, or type of reactive group inserted. The permeability of the chitosan-alginate capsules was assessed, with various diffusing proteins. Membranes formed with chitosan Mv =0.5 × 106 excluded beta amylase, suggesting a membrane molecular weight cut-off of approximately 200,000.

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Rhodiola rosea L. (Crassulaceae), also known as golden root or rose root, is a perennial herbaceous plant widely distributed at high altitudes in the arctic and mountainous regions throughout Europe and Asia. The roots of R. rosea are traditionally used as a tonic and adaptpgen in Russia, and also as a hemostatic in Tibetan folk medicine. Various pharmacological effects of the roots of R. rosea have been reported, such as improvement of the memory and learning abilities, anti-stress and anticancer effects, etc.1,2) Previous chemical investigation on R. rosea has demonstrated the occurrence of over thirty compounds, belonging to the phenylethanoids, phenylpropanoides, flavonoids, phenolic acids, cyanoglycosides, monoterpenoids, and triterpenes. [1][2][3][4][5] Although several monoterpenoids have been reported in other Rhodiola species, 6,7) only one monoterpenoid, rosiridol and its glucoside, rosiridin have been isolated from R. rosea. 3,8) Our continuing phytochemical investigations on Chinese medicinal plants [9][10][11][12] have resulted in the isolation of five new monoterpene glycosides, rhodiolosides A-E (1-5) from the roots of R. rosea. This paper deals with the isolation and structure elucidation of these new compounds. Results and DiscussionThe air-dried roots of R. rosea were extracted with 80% aqueous EtOH. The extract was concentrated, suspended in H 2 O and then partitioned successively with CHCl 3 , EtOAc and n-BuOH. The n-BuOH-soluble fraction was evaporated under reduced pressure and fractionated using silica gel and ODS columns. Further purification by repeated reversedphase HPLC afforded five new monoterpene glycosides, rhodiolosides A-E (1-5).Rhodioloside A (1) was isolated as a colorless viscous oil. The molecular formula was established as C 16 H 28 O 8 by highresolution (HR)-FAB-MS. On acidic hydrolysis, 1 afforded D-glucose, which was identified by gas-liquid chromatography (GLC) analysis of its trimethylsilyl thiazolidine derivative. 13 The

The coordinated development of industrialization and its ecological environment are vital antecedents to sustainable development in China. However, along with the accelerating development of industrialization in China, the contradiction between industrial development and environment preservation has turned out to be increasingly evident and inevitable. Eco-efficiency can be seen either as an indicator of environmental performance, or as a business strategy for sustainable development. Hence, industrial eco-efficiency promotion is the key factor for green industrial development. This study selects indicators relevant to resources, economy, and the environment of industrial development, and the indicators can well reflect the characteristics of industrial eco-efficiency. The SBM (Slacks-Based Measure) model overcomes the limitations of a radial model and directly accounts for input and output slacks in the efficiency measurements, with the advantage of capturing the entire aspect of inefficiency. This study evaluates the industrial eco-efficiency of nine cities in Fujian province during the period of 2006–2016, based on undesired output SBM (Slacks-Based Measure) model and also uses a Tobit regression model to analyze the influencing factors. The results show that there is a positive correlation among the economic development level, opening level, research and development (R&D) innovation, and industrial eco-efficiency in Fujian Province. However, a negative correlation was found between the industrial structure and industrial eco-efficiency in Fujian Province. Moreover, environmental regulation in Fujian Province was not found to significantly influence the industrial eco-efficiency. Hence, through the systematic analysis of industrial eco-efficiency and its influencing factors in Fujian, the study gives further insight on how policy-making can help achieve sustainable development, balancing between economic benefits and ecological improvements.

The secondary structure and compliance of a novel small caliber (≤6 mm) silk fibroin (SF) tubular scaffold (SFTS) were investigated. Imitating the structure of natural vascular tissue, the SFTS consisted of a silk knit as the medium and a poly(ethylene glycol) diglycidyl ether (PEG-DE) cross-linked silk fibroin (SF) membrane as the intimal and adventitial layers, integrated to form a porous tissue. FTIR and XRD results showed that PEG-DE could induce SF molecules to form β-sheets during the cross-linking reaction process, resulting in improved crystallinity. As a result of the silk knit medium the SFTS had excellent mechanical properties. The intimal layer, which is in contact with a continuous flow of blood, must have adequate compliance. The results showed that the intimal layer of the SFTS had good stress-strain resistance when combined with the silk knit medium. When the SFTS was prepared with 6% SF, its axial breaking strength was >62 kPa and breaking elongation could reach about 33%; the circumferential breaking strength was >10 MPa and breaking elongation was >18%. The results of compression testing showed that the radial compression resilience of SFTS reached 94%, which was a significant improvement on commercial artificial blood vessels prepared from Dacron.