Effect of E-waste copper alloy additions on the microstructure and organization of Cu90PSn brazing joints.

The effects of different contents of e-waste alloy on the microstructure and joint properties of Cu90PSn brazing filler metal was investigated during copper and copper brazing. Microstructure of base metal and brazing filler metal was studied with scanning electronic microscopy (SEM). The properties of brazing joint obtained by adding different electronic waste filler metal for smelting copper alloy were compared together. The results indicated that the fluidity of Cu90PSn brazing filler metal was weakened and the spreading property of Cu90PSn brazing filler metal was damaged after the addition of e-waste copper alloy. The structure of Cu90PSn brazing filler metal is mainly composed of (Cu), Cu3P and (Cu,Sn) compounds. When a small amount of electronic waste copper alloy is added, a trace amount of Fe in the brazing filler metal is distributed in the matrix structure of the filler metal in the form of solid solution. With the increase of copper alloys contents by smelting e-waste, Fe content in Cu90PSn brazing filler metal increases; the granular Fe3P phosphide changes into lamellar form. The Cu3P compound phase changes from continuous large orderly arrangement to discontinuous small block structure. Therefore, adding a trace amount of electronic waste copper alloy to the solder induction brazing copper/copper can obtain a uniform composition of the brazing structure. And the welding performance is not affected. However, As the content of e-waste smelted copper alloy continues to increase, the tensile strength shows a downward trend, which is attributed to the presence of brittle compound Fe3P in the joint.

Coupling optimization with territorial LCA to support agricultural land-use planning.

The life cycle assessment framework was adapted to the territorial level (the "territorial LCA") to assess the environmental impacts and services of land-use planning scenarios. Given the various geographical conditions of the territory, the potential alternatives of land-use scenarios could be enormous. To prevent the iterative process of proposing and comparing alternative scenarios, this work aims to move one step further to automatically generate optimal planning scenarios by linking the novel territorial LCA with multi-objective optimization (MOO). A fuzzy optimization approach is adopted to deal with the trade-offs among objectives and to generate optimized scenarios, minimizing the environmental damages and maximizing the satisfaction level of the desired land-use functions subjected to constraints such as area availability and demand. Geographical Information System (GIS) is employed to manipulate geographic datasets for spatial assessment. An illustrative case study tests the novel integrated method (the territorial LCA, MOO, and GIS) on its ability to propose optimal land-use planning for bioenergy production in a region in Belgium. The study results reveal the competition of land uses for different energy products, the trade-offs among impact categories, and potential impacts on other territories if implementing optimal land planning for the territory under study. The optimization outcomes can help decision-making on the optimal locations for different crop types (i.e., miscanthus, willow, and maize in the case study) and utilizations (i.e., electricity, heat, biogas, and bioethanol in this study) complying with the objectives and constraints. This integrated tool holds the potential to assist policymakers when deciding on how to use the territory facing the global context of increasing demands for multiple uses of bio-based products, such as for food, feed, fuel, fiber, and chemicals. Limitations of the current method and its potential for real-world applications are discussed, such as expanding the scope to include life cycle sustainability assessment and taking farmers' behavior and crop rotation into account.

A simple, rapid, economical, and practical method for the determination of efavirenz in plasma of Chinese AIDS patients by reverse phase high-performance liquid chromatography with ultraviolet detector.

This study aimed to develop a reverse phase high-performance liquid chromatographic (RP-HPLC) method for the determination of efavirenz in human plasma and to use it for determining the concentrations of efavirenz in Chinese AIDS patient. A simple mobile phase consisting of 0.01 mol/L NaH2PO4 solution and acetonitrile (38:62, V/V) was pumped at a flow rate of 1.0 mL/min through a reverse phase Diamonsil C18 column maintained at 30°C. Diazepam was used as an internal standard and monitored with efavirenz at 247 nm. The protein of 100 µL plasma sample was precipitated before 20 µL of the supernatant was directly injected into the column. The linear response over the concentration ranges 0.10-20.0 µg/mL was obtained and the linear regression equations was Y = 2.2873X ‒ 0.1449 (r = 0.9999). The intra-day and inter-day precisions (1.9-2.6%, 2.2-7.2%, respectively), the relative and absolute recovery (99.3-106.3%, 75.6-80.3%, respectively) met the international standards. Stability of plasma samples were evaluated for short-term (ambient temperature for 16 h) and long-term (-20°C for 30 days) storage conditions and were found to be stable. The mean plasma concentration of efavirenz of the 406 patients was 2.21 ± 1.95 µg/mL, 77.3% of which were within the therapeutic window (1-4 µg/mL), 15.1% were below the window, and 7.6% were over it. In conclusion, the method had advantages of convenience, rapidity, necessary accuracy and precision, high practicality and met the needs for therapeutic drug monitoring and the pharmacokinetic study of efavirenz, especially in underdeveloped countries. For Chinese AIDS patients, it was beneficial to use efavirenz under the guidance of therapeutic drug monitoring.