手榴弹与小口径炮弹移动式销毁系统

为解决对小量零散弹药销毁的问题,设计一种手榴弹与小口径炮弹移动式销毁系统。分别对小口径炮弹、木柄手榴弹和无柄手榴弹分解机进行分析,采取自动控制技术、自动检测技术和安全措施控制,对分解机进行功能整合优化设计,实现系统的全部功能并保证有足够的操作维修空间。实际应用结果表明:该设计保证了弹药销毁的可靠性和安全性,具有良好的推广前景。

转盘式粉末药型罩自动生产专机

为提高油井射孔弹穿孔性能,设计一种转盘式粉末药型罩自动生产设备。详述转盘式粉末药型罩自动生产专机的组成,通过控制转盘转速变化实现精加料,采用液压马达及油量伺服控制系统,对旋压机构进行设计,确保产品密度均匀性,并对设备进行应用验证。应用结果表明:该设备实现了粉末药型罩的全自动化生产,提高了生产效率和产品质量。

某款汽油机进气道偏移对发动机的影响

文章对不同偏移量的气道进行气道稳态试验和发动机台架试验,得到气道流量系数,发动机扭矩、油耗、排放数据,得出满足要求的气道参数,为后续生产提供依据。

DFT study of CO_(2)electrochemical reduction on two-dimensional metal-based covalent organic frameworks

CO_(2)electrochemical reduction(CO_(2)ER)to high-value fuels and chemicals is a promising strategy for using CO_(2)as a carbon source.However,the large-scale application of CO_(2)ER is limited by the lack of efficient and selective electrocatalysts.By means of density functional theory(DFT)calculations,the potential of transitional metal-based covalent organic frameworks(TM-COFs,TM=Fe,Co,Ni,Cu,Zn,Ru,Rh,Pd,and Ag)as CO_(2)reduction electrocatalysts was systematically studied.The results show that the single TM atom can be firmly anchored on COFs for forming stable single-atom catalysts.The TM atom in phthalocyanine has excellent catalytic activity towards CO_(2)ER,while the pyridine N in pyrazine is the active site of the hydrogen evolution reaction(HER).Among studied candidates,Co-COF and Rh-COF are predicted to have limiting potential of-0.66/-0.11 and-0.49/-0.49 V for CO_(2)ER/HER,respectively.The present study may provide a new strategy for designing novel bifunctional catalysts.

The comparative investigation on redox property and second-order nonlinear response of Keggin-type α-[PM_(12)O_(39)NPh]^(3-) (M = W and Mo) and Mo_6NPh

Keggin-type phenylimido-polyoxometalates α-[PM12O39NPh]3- (M = W and Mo) have been systematically investigated on the electronic structures, redox as well as nonlinear optical (NLO) properties by density functional theory (DFT). The strong M≡N bond confirmed by natural bond orbital (NBO) analysis comprises one σ bond and two π bonds, the same as Mo≡N in [Mo6O18NPh]2-. Furthermore, phenylimido segment effectively modifies the electronic properties of α-[PM12O39NPh]3-. On one hand, when enlarging the inorganic cluster from {Mo6O18} to {PMo12O39}, the energy gap between HOMO and LUMO in α-[PMo12O39NPh]3- decreased, resulting in enormously anodic shift for the reduction potential, while the excitation energy is less and the total second-order polarizability β0 is up to 438.3×10?30 esu, which is nearly 10 times larger than that of [Mo6O18NPh]2-. On the other hand, when metal W in α-[PM12O39NPh]3- is substituted by Mo, the interaction between Mo and N is enhanced and the redox ability becomes stronger. The β0 value for α-[PMo12O39NPh]3- is more than 5 times higher than that of α-[PW12O39NPh]3?. It indicates that changing appropriate metal or enlarging the inorganic cluster will improve the redox properties and second-order nonlinear response. Moreover, the electron transition for three compounds mentioned above occurred mainly from organoimido segment (as the electron donor) to polyanion cluster (as the acceptor). As a result, α-[PMo12O39NPh]3- may be a promising candidate for oxidant and nonlinear optical material.

Electronic properties and stabilities of methoxy-substituted Lindqvist polyoxometalates [Nb_2W_4O_(19)CH_3]^(3-) by DFT

The electronic properties and stabilities of five [Nb2W4O18OCH3]3-isomers have been investigated using a density functional theory method.The results show that the isomer with the methoxy group occupying a bridging position between two tungsten atoms(two tungsten atoms in the plane that contains two niobium atoms) in the [Nb2W4O18OCH3]3-framework is the most stable isomer in acetonitrile.The stability of the one-electron-reduced isomers changes little.The most stable one-electron-reduced isomer has the methoxy group occupying a bridging position between niobium atoms in the [Nb2W4O18OCH3]4-framework.The M-Ob(M = Nb,W;b denotes bridging) bond lengths in anions in which the metal atoms are connected by a methoxy group are longer than those in [Nb2W4O19]4-.The highest occupied molecular orbitals(HOMO) in [Nb2W4O19]4-mainly delocalize over the bridging oxygen atoms of two niobium atoms and two tungsten atoms located in the equatorial plane,and the bridging oxygen atoms on the axial surface.The lowest unoccupied molecular orbitals(LUMO) of [Nb2W4O19]4-are mainly concentrated on the tungsten atoms and antibonding oxygen atoms.Methoxy substitution modifies the electronic properties of the [Nb2W4O18OCH3]3-isomers.The HOMOs in the five isomers formally delocalize over the bridging oxygen atoms,which are distant from the surface containing the methoxy group and four metal atoms.The LUMOs delocalize over the d-shells of the four metal atoms that are close to the methoxy group,and the p-orbitals of oxygen.One-electron reduction occurred at the tungsten atoms,not the niobium atoms.

Exploration on Charge Transfer and Absorption Spectra of Spiro[fluorene-9,90-xanthene]-based Polyoxometalate Hybrids Toward High Performance Dye-sensitized Solar Cell

Based on spiro[fhiorene-9,90-xanthene]（SFX, dye 1）, the Lindqvist-type polyoxometalate（POM） functio- nalized with SFX and its derivatives（dyes 2--4） used in dye-sensitized solar cells（DSSCs） were designed and inves- tigated with the density functional theory（DFT） and time-dependent DFT（TD-DFT） calculations. The results indicate that Lindqvist-type POM is the main contribution to the lowest unoccupied molecular orbital（LUMO） and affects the LUMO energies of dyes 2--4. The maximum absorptions of the designed dyes containing POM（dyes 2--4） are red shifted comparing with that of dye 1. The introduction of electron-donating group onto SFX segment is helpful to red shift the absorption spectra. The major factors affecting the performance of DSSCs, including light harvesting and electron injection were evaluated. Considering the absorption spectra and photovoltaic parameters, dyes 3 and 4 are promising high performance dye sensitizers in n-type DSSCs.