Guanidinium-based covalent organic framework membrane for single-acid recovery

Article discusses how, although acids are extensively used in contemporary industries, time-consuming and environmentally unfriendly processes hinder single-acid recovery from wastes containing various iconic species. The authors rationally designed a membrane with uniform angstrom-sized pore channels and built-in charge-assisted hydrogen bond donors that preferentially conducted HCl while exhibiting negligible conductance for other compounds

The GABBR1 locus and the G1465A variant is not associated with temporal lobe epilepsy preceded by febrile seizures

BACKGROUND: Polymorphism G1465A in the GABBR1 gene has been suggested as a risk factor for non-lesional temporal lobe epilepsy (TLE); however, this genetic association study has not been independently replicated. We attempted to replicate this study in our cohort of patients with TLE. Furthermore, we also analyzed the coding sequence of this gene and searched for disease-causing mutations. METHODS: We included 120 unrelated individuals with TLE that was preceded by febrile seizures (FS) who did not have any evidence of structural lesions suggesting secondary epilepsy. 66 individuals had positive family history of TLE epilepsy and 54 were sporadic. Each patient was genotyped for the presence of G1465A polymorphism. All exons of the GABBR1 gene were screened by single strand confirmation polymorphism method. Genotypes were compared with two independent matched control groups. RESULTS: We detected two A alleles of the G1465A polymorphism in one homozygous control subject (0.87% of all alleles) and one A allele in a patient with TLE (0.45%, not significant). Other detected polymorphisms in coding regions had similar frequencies in epilepsy patients and control groups. No disease causing mutations in the GABBR1 gene were detected in patients with sporadic or familial TLE. CONCLUSION: Our results indicate that TLE preceded by FS is not associated with the polymorphisms or mutations in the GABBR1 gene, including the G1465A polymorphism. The proportion of TLE patients with FS in the original study, reporting this positive association, did not differ between allele A negative and positive cases. Thus, our failure to reproduce this result is likely applicable to all non-lesional TLE epilepsies

Economies of scale analysis and location studies for fuel ethanol refineries

The development of commercial-scale cellulosic ethanol refineries is a challenging task, but it is a promising way to increase national energy independence and security. The main barrier to this development is high production costs. Biomass feedstock costs account for more than 30% of the total operational cost. The Area Utilization Factor (AUF) is a significant index representing the amount of agricultural residues or energy crops that can be collected and delivered to ethanol facilities. Most biomass studies have used fixed AUF values for feedstock procurement. However, plant location can greatly impact feedstock procurement cost. In addition, it is difficult to estimate biomass feedstock costs, since no large-scale commercial markets exist. It is, therefore, not easy to make plant siting decisions, as several factors need to be considered and evaluated. The objectives of this study are: (1) to build a base process and cost model and to conduct an economies of scale analysis for a cellulosic ethanol refinery, and. (2) to find an effective way to determine optimal plant size and location. To model biomass feedstock more practically, the AUF was assumed to be normally distribution, with the mean increasing with distance from the refinery. SuperPro Designer was used to build the process model using the dilute-acid prehydrolysis and enzymatic hydrolysis method. The process model was then used to conduct the economies of scale analysis and determine the optimal plant size. For plant site selection, suitability analyses to identify the candidate plant locations were conducted by examining the relative significance of siting criteria. In addition, a GIS tool was integrated with a grid analysis method and a mixed-integer programming model to determine the optimal plant locations. An engineering process model was built for the economies of scale analysis for cellulosic ethanol production. For feedstock procurement, normally-distributed AUFs resulted in more practical solutions than AUFs conforming to uniform or sine wave distributions. The result of economic analysis suggests that refineries are better off to employ the contract pricing method. Optimally, plants should be located in areas with easy access to transportation facilities, low water cost, low corn basis and high feedstock yield. In future work, the process and cost model need to be updated to use newer versions of SuperPro Designer. More effort need to be put on the selection of AUF distribution functions, since normal distributions may not best represent AUF variations. The study region, herein limited to local watersheds, need to be expanded to the entire Midwest or the whole country

Simplified Calculation Model and Experimental Study of Latticed Concrete-Gypsum Composite Panels

In order to address the performance complexity of the various constituent materials of (dense-column) latticed concrete-gypsum composite panels and the difficulty in the determination of the various elastic constants, this paper presented a detailed structural analysis of the (dense-column) latticed concrete-gypsum composite panel and proposed a feasible technical solution to simplified calculation. In conformity with mechanical rules, a typical panel element was selected and divided into two homogenous composite sub-elements and a secondary homogenous element, respectively for solution, thus establishing an equivalence of the composite panel to a simple homogenous panel and obtaining the effective formulas for calculating the various elastic constants. Finally, the calculation results and the experimental results were compared, which revealed that the calculation method was correct and reliable and could meet the calculation needs of practical engineering and provide a theoretical basis for simplified calculation for studies on composite panel elements and structures as well as a reference for calculations of other panels

Research on Seismic Test and Calculation Model for Improving Factor of Composite Board with Heat Preservation Function

Since the composition and stress state of thermal-insulation composite plates are extremely complex, it is difficult to conduct calculation using conventional methods. Further calculation on its composition structure is even more difficult. To settle this difficulty, this paper conducted experimental investigations on thermal-insulation composite plate and conventional composite plates, and a simplified calculation method with improved factors was deduced based on the experimental results. In this study, the influence of nonstructural thermal insulation system on the composite plate was specially considered. The calculated expressions are deduced, while the stiffness and damping (properties) are determined. Case analysis was carried out to validate the reliability and accuracy of the simplified calculation method of improvement factor. The research results indicate that the modeling difficulty and computational effort are greatly reduced, with relatively small errors. Hence, it is beneficial to the calculation and analysis of composite plates and global structures

Seismic Experimental Study on New-Type Composite Exterior Wallboard with Integrated Structural Function and Insulation

In order to evaluate the seismic performance of new-type composite exterior wallboard, a total of six exterior and interior wallboards were incorporated in the experiment of seismic performance. Seismic performance such as the stress process, damage mode, hysteresis and skeleton curve, load-carrying and ductility coefficient, damping and energy dissipation, stiffness degradation as well as material strain of the exterior wallboards were analyzed with emphasis and compared with interior wallboards. Results of the experiment and analysis showed that both interior and exterior wallboards exhibited outstanding seismic performance. Due to the existence of insulation layer and externally bonded single gypsum board, the capacity of elastoplastic deformation and seismic energy dissipation of the exterior wallboards was improved and each seismic performance indicator of the exterior wallboards outperformed the interior wallboards

Seismic Performance Test of Double-Row Reinforced Ceramsite Concrete Composite Wall Panels with Cores

The research objective of this study was the seismic performance of double-row reinforced ceramsite concrete sandwich wall panels. The feasibility of upgrading a new wall panel from a non-load-bearing partition wall to a load-bearing seismic wall was examined by conducting cyclic load tests on five wall panel specimens. The test piece was a sandwich thermal insulation structure that could achieve a good protection distance between the thermal insulation material and the fire source so that the fire prevention problem could be solved. At the same time, the problem of easy fall-off of the insulation system was also solved. The specimens were divided into three groups, including three double-row reinforced ceramsite concrete sandwich wall panels with different dosages of alkali-resistant glass fiber, a double-row reinforced ordinary concrete sandwich wall panel, and a solid concrete ceramic wallboard. The effects of different dosages of alkali-resistant glass fiber, construction forms, and bearing side plate materials on the seismic performance of the sandwich wall panels were investigated separately for the specimens. From the analysis of the specimen results (damage characteristics, hysteresis curves, energy dissipation capacity, bearing capacity, ductility, longitudinal reinforcement strain, and stiffness degradation), it could be seen that among the five types of wallboard, the double-row reinforced ceramsite concrete sandwich wall panel with 0.3% fiber content had the best ductility and energy dissipation capacity. Adding fiber could solve or improve the problem of the low ultimate bearing capacity of ceramsite concrete as the wallboard’s bearing material. Compared with the same size solid ordinary concrete wallboard, the bearing capacity of the double-row reinforced ceramic concrete sandwich panel was slightly reduced. However, the additional seismic performance indexes were relatively superior. Through the analysis of the test results, it was shown that, when considering the thermal performance and seismic capacity, the new wall panel had good prospects for engineering applications

Experimental Study of Gypsum-Concrete Dense-Column Composite Boards with External Thermal Insulation Systems

In this paper, a new kind of gypsum-concrete dense-column thermal insulation composite board was developed, with seismic tests conducted on three specimens under quasi-static loading conditions. The fracture feature, hysteresis behavior, material strain, load-bearing and deforming capacity, and energy-dissipating capacity of the composite board were analyzed. The results indicated that this composite board has a favorable energy-dissipating capacity, i.e., relatively high seismic performance. By comparing with the experimental results of composite boards without thermal insulation systems, the influence regularity of thermal insulation system on the deformation behavior of composite board was investigated. The comparison result indicated that with a thermal insulation system, the bearing capacity and ductility of composite board are obviously increased, implying that the thermal insulation system is beneficial for the seismic performance of composite boards

Study on Seismic Behaviors of the Pagoda in Songyue Temple

The dynamic properties and anti-earthquake behaviors of Pagoda in Songyue Temple was studied by numerical simulation method. Firstly, based on the its contexture, the equivalent model reflecting the force transfer mechanism is established. Secondly, by analyzing the dynamic characteristics of the computational model, the vibration modes, natural vibration frequency and natural period of vibration are measured. The correctness of the model verified by comparing the theoretical calculation results and the simulation results. Lastly, the seismic behaviors of the Pagoda in Songyue Temple was evaluated according to the elastic spectrum analysis and time-history analysis results and related data. The results show that: the stiffness is uniformly distributed and the seismic performance is good enough. Under the action of earthquake force, it is easy to produce tension rupture and the tacha, the pagoda body without section change, as weak link of the structure, need to focus on