Isolation and characterization of wood components with aqueous acetic acid

A study was conducted on the isolation of poplar （Populusxeurarnaricana （Dode） Guineir cv. I -72/58） wood components with aqueous acetic acid （AcOH） containing small amounts of sulfuric acid. The reaction time, concentration of acetic acid, ratio of liquor to wood, and concentration of acid catalyst were investigated to examine their effects on the fractionation of wood components. The three main separated components were characterized. The results showed that the optimum conditions for fractionation of poplar wood components were： 0.3% H2SO4 in reaction solution, ratio of liquor to wood 6, reflux time 3 h, and 90% AcOH. The residues were mainly composed of a-Cellulose and hemicellulose, The water insoluble precipitate （acetic acid lignin, AcL） had a low weight-average molecular weight range from 341 to 253 （Mw） and a narrow molecular weight distribution from 1.1 to 1.2. The sugar analysis revealed the solubilized products resulted mainly from hemicellulose and exited as monosaccharides.

Recycling and recovery of spent copper-indium-gallium-diselenide(CIGS)solar cells:A review

Copper-indium-gallium-diselenide(CIGS)is a fast-evolving commercial solar cell.The firm demand for global carbon reduction and the rise of potential environmental threats necessitate spent CIGS solar cell recycling.In this paper,the sources and characteristics of valuable metals in spent CIGS solar cells were reviewed.The potential environmental impacts of CIGS,including service life,critical material,and material toxicity,were outlined.The main recovery methods of valuable metals in the various types of spent CIGS,including hydrometallurgy,pyrometallurgy,and comprehensive treatment processes,were compared and discussed.The mechanism of different recovery processes was summarized.The challenges faced by different recycling processes of spent CIGS were also covered in this review.Finally,the economic viability of the recycling process was assessed.The purpose of this review is to provide reasonable suggestions for the sustainable development of CIGS and the harmless disposal of spent CIGS.

Research and Application Progress of Straw

Straw is a general term for the stem and leaf parts of mature crops,and is a multi-purpose renewable biomass energy resource in the agricultural ecosystem.The prospect of comprehensive utilization of straw has become broad with the development of agricultural production,the advancement of science and technology,and the improvement of the level of agricultural mechanization.The comprehensive utilization of straw plays an important role in enhancing the sustainable development ability of agricultural economy and improving the current situation of comprehensive utilization of agricultural resources in my country.This paper briefly combs the development history of straw and the prospect and current situation of comprehensive utilization,and expounds the separation technology of straw components,straw man-made panels,straw concrete,straw returning technology and oyster mushroom cultivation.It focuses on the description of the component separation technology of straw and the manufacturing process of straw-based panels.The different separation methods and separation effects of cellulose,hemicellulose and lignin were introduced in detail,and the static yield strength(MOR),internal bonding strength(IB)and water absorption thickness of several common straw-based panels were compared and studied(TS).Finally,it summarizes the benefit analysis of the comprehensive utilization of straw by scholars from the perspective of economics,and summarizes the corresponding measures based on their own views.

A Preliminary Study on Biological Activity of Wikstroemia chamaedaphne Meissn

[ Objective ] The insecticidal and antibacterial bioactivity of Wikstroemia chamaedaphne Meissn were screened and bioactive substances in it were separated and purified. [ Method] The Wikstroemia chamaedaphne Meissn was conducted ultrasonic extraction in petroleum ether, ethyl acetate and methanol. The insecticidal activity of Wikstroemia chamaedaphne Meissn to Mythimna separata walker and aphid were determined. The antibacterial activity of Wikstroemia chamaedaphne Meissn to Fusarium graminearu, Glomerella cingulata, F. oxysporium f. sp niveum, Alternaria solani and Fusarium oxysporium were also determined. The bioactivity-guided methods such as opencolumn chromatography and Pre-HPLC method were used to separate active components in petroleum ether extract from Wikstroemia chamaedaphne Meissn. [ Result] When the concentration was 500 mg/L, 3 kinds of extracts from Wikstroemia chamaedaphne Meissn didn＇ t show obvious antibacterial bioactivity to 5 kinds of test samples. When the concentration was 5%, petroleum ether extract show certain topical toxicity to aphids. The ethyl acetate extract showed certain antifeedant activity to 3^rd instar Larvae of Mythimna separata Walker. The fraction F4 of petroleum ether extract possessed highest topical toxicity to aphids and the lethality was 60.00%. [ Conclusion] Wikstroemia chamaedaphne Meissn contained many insecticidal constituents whose active parts and mechanism were needed further researches.

New advances in coal structure model

Although human beings have come to understand and utilize coal for a very long history, no theoretical breakthrough in the study of coal structure has been made, which still needs continuous efforts of coal chemical workers. Based on the viewpoint of ‘vague/clear', the species classification and accurate analysis on coal were conducted by using the natural clustering all-component separation method. A more systematic and detailed coal embedded structure model theory which is suitable for coal of all ranks was developed from the previous one and a more complete theoretical system about the component and structure of coal was constructed. The whole establishment process of the theory was summarized and some of the main support data and analysis test results, including TEM, AFM, FTIR, GC/MS, MALDI/TOF/MS, DART/MSD, fractal analysis and so on were provided. The coal embedded structure theory fully considers both the identity and the particularity of all-rank coal, reflects the coal component and structure in the full range of coal rank, solves the systematic cognitive problem of coal component and structure on macro and micro level, and provides a valuable and meaningful theoretical approach for the coal processing and conversion technology.

RESEARCH OF QUANTUM GENETIC ALGORITH AND ITS APPLICATION IN BLIND SOURCE SEPARATION

This letter proposes two algorithms: a novel Quantum Genetic Algorithm (QGA)based on the improvement of Han's Genetic Quantum Algorithm (GQA) and a new Blind Source Separation (BSS) method based on QGA and Independent Component Analysis (ICA). The simulation result shows that the efficiency of the new BSS method is obviously higher than that of the Conventional Genetic Algorithm (CGA).

Single channel signal component separation using Bayesian estimation

A Bayesian estimation method to separate multicomponent signals with single channel observation is presented in this paper. By using the basis function projection, the component separation becomes a problem of limited parameter estimation. Then, a Bayesian model for estimating parameters is set up. The reversible jump MCMC （Monte Carlo Markov Chain） algorithmis adopted to perform the Bayesian computation. The method can jointly estimate the parameters of each component and the component number. Simulation results demonstrate that the method has low SNR threshold and better performance.

Measurment of gas-liquid two-phase slug flow with a Venturi meter based on blind source separation

We propose a novel flow measurement method for gas–liquid two-phase slug flow by using the blind source separation technique. The flow measurement model is established based on the fluctuation characteristics of differential pressure(DP) signals measured from a Venturi meter. It is demonstrated that DP signals of two-phase flow are a linear mixture of DP signals of single phase fluids. The measurement model is a combination of throttle relationship and blind source separation model. In addition, we estimate the mixture matrix using the independent component analysis(ICA) technique. The mixture matrix could be described using the variances of two DP signals acquired from two Venturi meters. The validity of the proposed model was tested in the gas–liquid twophase flow loop facility. Experimental results showed that for most slug flow the relative error is within 10%.We also find that the mixture matrix is beneficial to investigate the flow mechanism of gas–liquid two-phase flow.

The use of botulinum toxin A in chemical component separation: a review of techniques and outcomes

Fascial closure is crucial for abdominal wall reconstruction (AWR) but can be especially difficult in patients with massive ventral hernias or loss domain. Recently, botulinum toxin A (BTA) has been increasingly utilized as an adjunct in AWR to aid in fascial closure. This review aims to evaluate the current literature on the use of BTA in AWR to assess current treatment regimens, side effects, outcomes and complications. A literature search was performed, yielding 10 studies that met the inclusion criteria. There was a significant amount of heterogeneity in treatment regimens, with studies differing in BTA injection timing, dosage, concentration, and location. The majority of studies showed that injection of BTA preoperatively was able to augment abdominal wall musculature, with many showing a decrease in mean transverse defect size and high rates of successful fascial closure. No major complications were reported from BTA administration, with only mild side effects reported by some studies. The most common side effects include a weak cough or sneeze, bloating, and back pain, which generally all resolved prior to surgery. While BTA appears to be a promising adjunct for AWR, further investigation is needed to determine optimal patient selection and treatment regimens.

Posterior component separation/transversus abdominis release

The Rives-Stoppa technique for ventral hernia repair is commonly utilized due to well-proven outcomes with low overall morbidity. However, this approach is limited by the amount of myofascial advancement and sublay space available for a wide mesh overlap. Thus, anterior component separation was developed to allow further myofascial advancement.Some limitations were noted, which led to the subsequent study, utilization, and refinement of the posterior component separation (PCS) technique.PCS continues to demonstrate low hernia recurrence, surgical site occurrences, and improvement in rectus muscle function. Continued adoption of this technique has expanded to minimally invasive approaches for hernia repair. This paper is a comprehensive review of the evolution of PCS, technique, and outcomes.