Ionothermal synthesis of a three-dimensional zinc phosphate with DFT topology using unstable deep-eutectic solvent as template-delivery agent

A three-dimensional zinc phosphate compound with DFT topology, designated as ZnPO₄-EU1, has been synthesized by an ionothermal approach from the system HF-ZnO–P₂O₅-choline chloride-imidazolidone. Ethylenediamine, derived from decomposition of the imidazolidone component of the deep-eutectic solvent (DES) itself, is delivered to the synthesis and serves as an appropriate template for ZnPO₄-EU1. Experiments in which the synthesis conditions were varied showed that ZnPO₄-EU1 may be prepared over a wide molar ratio of P/Zn = 0.55–13.0. Powder X-ray diffraction patterns have been obtained at intervals to track the crystallization process of this material. The experimental data show that Zn₃(PO₄)₂ · 4H₂O (a dense phase) was first isolated from the DES after reaction for 1 h. Subsequently, the pure phase of ZnPO₄-EU1 was obtained with increasing crystallization time from 12 h to 72 h. The experimental results show that the nucleation and crystallization take place with relatively low levels of solvent degradation, demonstrating that zinc phosphate with a three-dimensional framework can be synthesized by in situ generation of an appropriate template using an unstable DES at high temperatures (150–200 °C).     

熟悉而又陌生

《Frame》总第46期向读者展示了许多有意思的想法和创意的细节下面是从中摘选出来的设计和空间方案他们都运用到了我们身边很熟悉的元素，在这里“腐朽”一下化神奇了。[编者按]     

Global practical stabilization of planar linear systems in the presence of actuator saturation and input additive disturbance

In this note, we revisit the problem of global practical stabilization for planar linear systems subject to actuator saturation and input additive disturbances. A parameterized linear state feedback law is designed such that, by tuning the value of the parameter, all trajectories of the closed-loop system converge to an arbitrarily small neighborhood of the origin in a finite time and remain in there.     

A Tutorial on GrÖbner Bases With Applications in Signals and Systems

This paper is a tutorial on GrÖbner bases and a survey on the applications of GrÖbner bases in the broad field of signals and systems. A reasonably detailed review is given of several fundamental theoretical issues that occur in the use of GrÖbner bases in multidimensional signals and systems applications. These topics include the primeness of multivariate polynomial matrices, multivariate unimodular polynomial matrix completion, and prime factorization of multivariate polynomial matrices. A brief review is also presented on the wide-ranging applications of GrÖbner bases in multidimensional as well as one-dimensional circuits, networks, control, coding, signals, and systems and other related areas like robotics and applied mechanics. The impact and scope of GrÖbner bases in signals and systems are highlighted with respect to what has already been accomplished as a stepping stone to expanding future research.      

国产陶瓷膜清洗方法的探讨

本文结合生产实际 ,介绍陶膜的清洗工艺 ,并通过比较试验获得优化的清洗方案。     

15000 m^3／h制氧机组同步电动机起动技术研究

介绍液态软起动技术在济钢 15000 m3/h制氧机配套的 6000 kW同步电动机上的应用情况,阐述了系统的原理、特点、仿真计算及实际应用后达到的效果.     

Photoluminescence and X-ray Diffraction of Distributed Bragg Reflector

Spectral and structural characteristics of distributed Bragg reflector (DBR) in vertical-cavity surface-emitting lasers were studied with photoluminescence and double- crystal X- ray diffraction measurement. The expected high quality epitaxial DBR structure was verified. In the X- ray double- crystal rocking curves of DBR the zeroth- order peak, the first and second order satellite peaks were measured. Splitting of diffraction peak appeared in the rocking curves was analyzed. The effects of introduced deep energy levels on the structural perfection and optical properties were discussed.     

钛制设备在焦化行业中的应用

介绍焦化行业钛设备的应用,剖析了分块式钛泡罩塔盘的结构特点,并对其经济性作了分析。     

Stream Classification System Based on Susceptibility to Algal Growth in Response to Nutrients

We developed a stream classification system that is based on stream’s susceptibility to algal growth using a two-step approach. The model portrays algal biomass as a result of stream’s response to nutrient concentrations and the response is governed by various stream factors. In the first step, a nutrient-chlorophyll a relationship was developed to characterize nutrient’s effects on algal biomass. Residuals of the relationship were attributed to stream’s susceptibility to algal growth in response to nutrients and referred to as “observed” susceptibility. In the second step, conditions of other contributing factors were used to explain the variation in the residuals and the developed relationship was used to generate “predicted” susceptibility. Existing data compiled from various monitoring projects of Illinois streams and rivers were used to illustrate the approach. Streams were classified into three (high, medium, and low) categories based on their observed and predicted susceptibility values, respectively. With the available data, the model showed a 40-50% success rate for classifying the streams based on three observed and predicted susceptibility categories. Model entropy also was calculated for selecting the best model. The results show the important role of both nutrients and other contributing factors in explaining the variation of algal biomass. The study also suggests ways to fine tune the model and improve its accuracy, which would make the presented model a more viable tool for stream classification for establishing nutrient criteria to prevent surface streams from eutrophication.