Photocatalytic degradation of methyl orange by Ca doped β-In2S3 with varying Ca concentration

Research on Chemical Intermediates - Industrial wastewater is becoming a universal environmental problem, wherein toxic organic compounds are important sources of pollution. For the degradation...     

A novel multi-claw reactive flame retardant derived from DOPO for endowing lyocell fabric with high effective flame retardancy

Cellulose - A novel DOPO derived multi-claw reactive flame retardant (DMCFR) was designed to improve the flame retardancy of lyocell fabric. The chemical structure of DMCFR was identified by proton...     

湍流大气传输中跟踪抖动对远场影响的仿真研究

分析了跟踪抖动对湍流大气传输远场光斑的影响。基于麦克斯韦电磁场理论,采用大气相干长度对大气湍流进行描述,推导了发射光束因跟踪抖动导致光轴偏离的远场表达式。在此基础上,利用相位屏法模拟抖动引起的倾斜相位和大气折射率起伏引起的相位调制,并采用低频补偿的功率谱反演法对传输过程进行了数值仿真。分析了不同跟踪抖动、湍流强度条件下远场光斑质心脱靶量的变化,以及不同尺寸模拟目标的回波概率。分析结果表明,在传输距离为10 km时,强湍流造成的远场光斑脱靶量可达几十μrad;当跟踪抖动较大时,湍流强弱对脱靶量影响差别很小。最后,对一定尺寸的模拟目标,从探测回波概率的角度给出了发射系统跟踪抖动量的控制范围。     

Numerical approach for the evolution of spin-boson systems and its application to the Buck–Sukumar model

We study the evolution properties of spin-boson systems by a systematic numerical iteration approach, which performs well in the whole coupling regime. This approach evaluates a set of coefficients in the formal expression of the time-dependent Schr?dinger equation by expanding the initial state in Fock space. This set of coefficients is unique for the spin-boson Hamiltonian studied, allowing one to calculate the time evolution from different initial states. To complement our numerical calculations, we apply the method to the Buck–Sukumar model. We find that when the ground-state energy of the model is unbounded and no ground state exists in a certain parameter space, the time evolution of the physical quantities is naturally unstable.     

Entropy of higher-dimensional charged Gauss–Bonnet black hole in de Sitter space

The fundamental equation of the thermodynamic system gives the relation between the internal energy, entropy and volume of two adjacent equilibrium states. Taking a higher-dimensional charged Gauss–Bonnet black hole in de Sitter space as a thermodynamic system, the state parameters have to meet the fundamental equation of thermodynamics. We introduce the effective thermodynamic quantities to describe the black hole in de Sitter space. Considering that in the lukewarm case the temperature of the black hole horizon is equal to that of the cosmological horizon, we conjecture that the effective temperature has the same value. In this way, we can obtain the entropy formula of spacetime by solving the differential equation. We find that the total entropy contains an extra term besides the sum of the entropies of the two horizons. The corrected term of the entropy is a function of the ratio of the black hole horizon radius to the cosmological horizon radius, and is independent of the charge of the spacetime.     

Soliton molecules and the CRE method in the extended mKdV equation

The soliton molecules of the(1+1)-dimensional extended modified Korteweg–de Vries(mKdV)system are obtained by a new resonance condition, which is called velocity resonance. One soliton molecule and interaction between a soliton molecule and one-soliton are displayed by selecting suitable parameters. The soliton molecules including the bright and bright soliton, the dark and bright soliton, and the dark and dark soliton are exhibited in figures 1–3, respectively.Meanwhile, the nonlocal symmetry of the extended mKdV equation is derived by the truncated Painlevé method. The consistent Riccati expansion(CRE) method is applied to the extended mKdV equation. It demonstrates that the extended mKdV equation is a CRE solvable system. A nonauto-B?cklund theorem and interaction between one-soliton and cnoidal waves are generated by the CRE method.     

基于PLC 的中央空调制冷系统变频控制研究

针对现有中央空调系统能源消耗严重的现状,基于可编程逻辑控制器(Programmable Logic Controller,PLC)对中央空调系统进行变流量节能改造。分析改造后中央空调系统的结构组成和变频运行原理,并提出适用于冷冻水泵和冷却水泵的分段速温差控制和PID温差控制设计方案。控制硬件选用三菱FX3U系列PLC和台达VFD-EL变频器,软件选用GX Work2编程软件及力控组态软件。将控制方案进行实验验证,实验结果表明,所设计的两种控制策略不仅跟随系统末端负荷变化快速达到稳定运行状态,提高运行能效比,而且节能效果显著,节能率分别为40.2%和48.7%。     

暗怪波的相互作用

以耦合非线性薛定谔方程为理论模型,数值研究了两个一阶暗怪波在正常色散单模光纤中的相互作用.基于一阶暗怪波精确解,采用分步傅里叶数值模拟法,从间距、相位差和振幅系数比方面讨论相邻两个一阶暗怪波之间的相互作用.基于二阶暗怪波精确解,讨论了两个一阶暗怪波的非线性相互作用.研究结果表明:同相位情况下,间距参数T1为0、5、20时,相邻两个一阶暗怪波相互作用激发产生“扭结型”暗怪波.相比较于单个暗怪波发生能量的弥散,“扭结型”暗怪波分裂形成多个次暗怪波.反相位情况下,间距参数T1为2、7、12时,相邻两个一阶暗怪波相互作用也可以激发产生“扭结型”暗怪波.并且“扭结型”暗怪波初始激发的空间位置偏离原始单个暗怪波的位置5.振幅系数比越大,该空间位置越接近5.二阶暗怪波可以看作是两个一阶暗怪波的非线性叠加,复合型和三组分型二阶暗怪波与相邻两个一阶暗怪波的相互作用略有相似.     

High Ethylene Selectivity in Methanol‐to‐Olefin (MTO) Reaction over MOR‐Zeolite Nanosheets

Precisely controlled crystal growth endows zeolites with special textural and catalytic properties. A nanosheet mordenite zeolite with a thickness of ca. 11 nm, named as MOR‐NS, has been prepared using a well‐designed gemini‐type amphiphilic surfactant as bifunctional structure‐directing agent (SDA). Its benzyl diquarternary ammonium cations structurally directed the formation of MOR topology, whereas the long and hydrophobic hexadecyl tailing group prevented the extensive crystal growth along b axis. This kind of orientated crystallization took place through the inorganic–organic interaction between silica species and SDA molecules present in the whole process. The thin MOR nanosheets, with highly exposed (010) planes and 8‐membered ring (MR) windows, exhibited a much improved ethylene selectivity (42.1 %) for methanol‐to‐olefin (MTO) reactions when compared with conventional bulk MOR crystals (3.3 %).