Self-Dual Permutation Codes over Finite Chain Rings

Permutation codes over finite chain rings are introduced; by using the character of the finite chain rings and the knowledge of representation of group, some conditions for existence or non-existence of self-dual permutation codes over finite chain rings are obtained. Specially, when the group is a direct product of a 2-group and a T-group, and the group action is transitive, the sufficient and necessary condition of the existence of permutation codes is given.

Octa-membered Water Ring Chain Based on Sulfonic Group in Ni(II) Complex with 2-[(E)-(2-Oxidophenyl)methyleneamino] Ethanesulfonato and 2,2′-Bipyridinyl

The title compound, [Ni（tssb）（2,2-bipy）2].5（H2O） 1 （tssbH2 =2-[（E）-（2-oxido- phenyl）methyleneamino]ethanesulfonato, 2,2-bipy = 2,2＇-bipyridinyl）, belongs to orthorhombic, space group Pbcn with a = 20.3983（18）, b = 17.6929（15）, c = 17.0897（15） nm, V= 6167.8（9） nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F（000） = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group.

Spin transport in a chain of polygonal quantum rings with Dresselhaus spin-orbit coupling

Using a transfer matrix method, we investigate spin transport through a chain of polygonal rings with Dresselhaus spin-orbit coupling（DSOC）. The spin conductance is dependent on the number of sides in the polygons. When DSOC is considered in a chain which also has Rashba spin-orbit coupling（RSOC） of the same magnitude, the total conductance is the same as that for the same chain with no SOC. However, when the two types of SOC have different values, there results a unique anisotropic conductance.

On Left A-Injective Rings

The main results of this paper are following theorems: (1)A left A-injective ring satisfying the ascending chain condition on right annihilator is QF ring. (2)A left A-injective ring satisfying the ascending hain condition on left annihilator is QF ring. (3)If R satisfies the following conditions: (ⅰ) r(A∩B)=r(A)+r(B), for each pair of left ils A,B;(ⅱ) rl(I)=I, for every right ideal I. Then R is semiperfect ring and has essential left s. In particular, any right CF left A-injective (or E(_RR) is projective left R-module) is QF ring

A unified analysis of a micro-beam,droplet and CNT ring adhered on a substrate:Calculation of variation with movable boundaries

In this study, we developed a general method to analytically tackle a kind of movable boundary problem from the viewpoint of energy variation. Having grouped the adhesion of a micro-beam, droplet and carbon nanotube （CNT） ring on a substrate into one framework, we used the developed line of reasoning to investigate the adhesion behaviors of these systems. Based upon the derived governing equations and transversality conditions, explicit solutions involving the critical parameters and morphologies for the three systems are successfully obtained, and then the parameter analogies and common characteristics of them are thor- oughly investigated. The presented method has been verified via the concept of energy release rate in fracture mechanics. Our analyses provide a new approach for exploring the mechanism of different systems with similarities as well as for understanding the unity of nature. The analysis results may be beneficial for the design of nano-structured materi- als, and hold potential for enhancing their mechanical, chemical, optical and electronic properties.

Bayesian Markov chain Monte Carlo inversion for anisotropy of PP-and PS-wave in weakly anisotropic and heterogeneous media

A single set of vertically aligned cracks embedded in a purely isotropic background may be con- sidered as a long-wavelength effective transversely iso- tropy （HTI） medium with a horizontal symmetry axis. The crack-induced HTI anisotropy can be characterized by the weakly anisotropic parameters introduced by Thomsen. The seismic scattering theory can be utilized for the inversion for the anisotropic parameters in weakly aniso- tropic and heterogeneous HTI media. Based on the seismic scattering theory, we first derived the linearized PP- and PS-wave reflection coefficients in terms of P- and S-wave impedances, density as well as three anisotropic parameters in HTI media. Then, we proposed a novel Bayesian Mar- kov chain Monte Carlo inversion method of PP- and PS- wave for six elastic and anisotropic parameters directly. Tests on synthetic azimuthal seismic data contaminated by random errors demonstrated that this method appears more accurate, anti-noise and stable owing to the usage of the constrained PS-wave compared with the standards inver- sion scheme taking only the PP-wave into account.

Droplet digital polymerase chain reaction assay for methylated ring finger protein 180 in gastric cancer

BACKGROUND Gastric cancer(GC)is one of the most prevalent malignant tumors that endangers human health.Early diagnosis is essential for improving the prognosis and survival rate of GC patients.Ring finger protein 180(RNF180)is involved in the regulation of cell differentiation,proliferation,apoptosis,and tumorigenesis,and aberrant hypermethylation of CpG islands in the promoter is strongly associated with the occurrence and development of GC.Thus,methylated RNF180 can be used as a potential biomarker for GC diagnosis.AIM To use droplet digital polymerase chain reaction(ddPCR)to quantify the methylation level of the RN180 gene.A reproducible ddPCR assay to detect methylated RNF180 from trace DNA was designed and optimized.METHODS The primer and probe were designed and selected,the conversion time of bisulfite was optimized,the ddPCR system was adjusted by primer concentration,amplification temperature and amplification cycles,and the detection limit of ddPCR was determined.RESULTS The best conversion time for blood DNA was 2 h 10 min,and that for plasma DNA was 2 h 10 min and 2 h 30 min.The results of ddPCR were better when the amplification temperature was 56°C and the number of amplification cycles was 50.Primer concentrations showed little effect on the assay outcome.Therefore,the primer concentration could be adjusted according to the reaction system and DNA input.The assay required at least 0.1 ng of input DNA.CONCLUSION In summary,a ddPCR assay was established to detect methylated RNF180,which is expected to be a new diagnostic biomarker for GC.

Design,Synthesis and Crystal Structure of Two One-dimensional Zigzag Chain-like Compounds

Two one-dimensional chain-like cyanide-bridged compounds, [Fe（Phen）2（CN）2Ni（Cyclam）]（ClO4）2·DMF-2H2O 1 （Cyclam = 1,4,8,11-tetraaza-cyclotetradecane, Phen = 1,10-phenanthroline, and DMF = N,N-dimethylformamide） and [Fe（Phen）2（CN）2Zn（Cyclam）]（PF6）2·CH3CN 2, were prepared by the reaction of [Fe（Phen）2（CN）2]·2H2O with M（Cyclam）^2＋ （M = Ni, Zn）. In complexes 1 and 2, the metal atoms are connected alternatively with CN groups. X-ray structure and IR analyses for 1 and 2 were performed. Structure analysis revealed that both complexes are centrosymmetric and the geometry around each metal atom is an octahedron. The two complexes crystallize in triclinic with space group of P^1-. For 1, a = 10.439（4）, b = 14.976（7）, c = 15.914（8）A,α = 83.168（15）, β = 74.338（15）, γ = 78.023（15）°, V = 2338.3（18）A^3, Z = 2, Mr = 1035.37, Dc = 1.471 g/cm^3, F（000） = 1076,μ = 0.895 mm^-1, the final R = 0.0616 and wR = 0.1414 for 5849 observed reflections （1 〉 2σ（I））. For 2, a = 9.656（6）, b = 15.404（9）, c = 15.822（10）A, α = 78.68（2）, β= 78.917（19）, γ = 77.15（2）°, V = 2223（2）A^3, Z = 2, Mr = 1064.87, Dc = 1.587 g/cm^3, F（000） = 1078,μ = 1.032 mm^-1, the final R = 0.0672 and wR = 0.1595 for 6819 observed reflections （I 〉 2σ（I））.

Phase behaviour of polyethylene knotted ring chains

The phase behaviour of polyethylene knotted ring chains is investigated by using molecular dynamics simulations. In this paper, we focus on the collapse of the polyethylene knotted ring chain, and also present the results of linear and ring chains for comparison. At high temperatures, a fully extensive knot structure is observed. The mean-square radius of gyration per bond （S2）/（Nb2） and the shape factor （（δ＊） depend on not only the chain length but also the knot type. With temperature decreasing, chain collapse is observed, and the collapse temperature decreases with the chain length increasing. The actual collapse transition can be determined by the specific heat capacity Cv, and the knotted ring chain undergoes gas-liquid-solid-like transition directly. The phase transition of a knotted ring chain is only one-stage collapse, which is different from the polyethylene linear and ring chains. This investigation can provide some insights into the statistical properties of knotted polymer chains.

Synchronization of N different coupled chaotic systems with ring and chain connections

Synchronization of N different coupled chaotic systems with ring and chain connections is investigated. The New system, the Chen system, the Lii system, the Lorenz system, and the Rossler system are used as examples in verifying effectiveness of the method. Based on the Lyapunov stability theory, the form of the controller is designed and the area of the coupling coefficients is determined. Simulations indicate that global synchronization of the N different chaotic systems can be realized by choosing appropriate coupling coefficients by using the controller.

“链-回-环”系统能质平衡核算及优化

文章以某球团厂200万t“链—回—环”系统为例,根据现场采集到的生产数据,核算得到该系统的热利用率为22.36%,余热回收率为71.62%。优化后得到当喷煤量在5.00~5.40 t/h,煤粉固定碳含量在76%~82%,煤粉燃尽率在97.5%以上时,预热Ⅱ段氧含量可以稳定在14.0%~16.0%,有利于球团矿的氧化且能有效抑制氮氧化物的生成。

Two New Chlorovanadates:Ba_8Cs_5V_8O_(24)Cl_(13)with[V_8O_(24)]Ring and MgCsV_2O_6Cl with[VO_3]_∞Chain

Two new crystals of chlorovanadates,Ba_8Cs_5V_8O_（24）Cl_（13）（1） and MgCsV_2O_6Cl（2）,were grown in the molten salt media. 1 crystallizes in tetragonal,space group P4/mmm（No. 123）,with a = 14.801（2）,c = 12.341（3） ？,V = 2703.5（8） ？~3,Z = 2,Mr = 3015.56,F（000） = 2640,μ = 11.044 mm-1,Dc = 3.704 g/cm3,the final R = 0.0380 and wR = 0.0937 for 1654 observed reflections with I 〉 2σ（I）. 2 crystallizes in a monoclinic space group C2/c（No. 15） with a = 11.128（2）,b = 10.540（2）,c = 6.9892（14） ？,β = 118.38（3）°,V = 721.2（2） ？~3,Z = 4,M_r = 390.55,F（000） = 712,μ = 7.997 mm-1,D_c = 3.597 g/cm^3,the final R = 0.0537 and w R = 0.1363 for 740 observed reflections with I 〉 2σ（I）. 1 exhibits a novel 8-membered-ring [V_8O_（24）] consisting of 8 corner-shared VO_4 tetrahetra,but in 2,an infinite ladder-like [VO_3]_∞ chain is formed by VO_5 square pyramids through sharing the edges.

Catalytic Ring Opening of Perhydroindan-Hydrogenolytic and Cationic Reaction Paths

Perhydroindan ( bicyclo [ 4.3.0 ] nonane )在六不同催化剂上在 5 MPa 的一个氢压力下面在一台流动类型仪器被变换，也就是在 bifunctional Pd/Na 上，H贝它沸石在 Ir/Na ， H-Y 和 Pt/Na 上，有 Br 的低集中的 H-Y 沸石? nsted 酸地点，并且在非酸的支持硅石上在三催化剂上包含三高贵金属。在 bifunctional 沸石 Pd/Na 上， H 贝它， perhydroindan 的骨胳的异构化是一枚 naphthenic 戒指开跟随的主要反应，在 ca 的低收益的开链的 nonanes 的形成。6% ，并且 hydrocracked 产品 C8- 。后者的碳数字分发没有与一枚 naphthenic 戒指显示 C9 先锋的 carbocationic 氢化裂解的 C1， C2， C7，和 C8 是塑造火山的。在 Ir/Na 上，到 C8- 的 H-Y 和 Pt/Na， H-Y (高效的戒指洞催化剂) ，戒指洞和氢化裂解在各自的金属上由 hydrogenolysis 发生了。五成员的戒指开比六成员的戒指开被发现快得多，与文学报告一致。开链的 nonanes (OCN ) 的最大的选择在 Ir/Na， H-Y 和 Pt/Na 上到达了， H-Y 很高， viz。分别地， 49% 和 54% 更好与是的 decalin 以前观察的开链的 decanes 比那些为烃建模。在 Pt/Na 上形成的 OCN， H-Y 更不比在 Ir/Na 上形成的那些被分叉，在两金属上以不同 hydrogenolysis 机制被解释的 H-Y。珍贵辅助机械学的信息在硅石上在三高贵金属上从 perhydroindan hydroconversion 的选择被获得。与 Pd/silica 相对照，红外 / 硅石和磅 / 硅石也给了 OCN 的可估计的选择，还这些选择的最大的价值比在二高效的沸石催化剂上获得的那些低。

Store Environment:Its Importance and Consumers'Expectations on Casual-wear Chain Stores in Honk Kong

This study attempted to examine the importance of storeenvironment in affecting consumers’store choice deci-sion;the relative importance among the three environ-mental factors;and consumers’expectations on store en-vironment for the casual-wear chain stores in HongKong.Julie Baker’s Three-category framework onstore environments namely ambient,design and socialfactors was adopted for investigation.The results indi-cated that the store environment was important in affect-ing consumers’selection of store for shopping.It alsorevealed that social factor was perceived relatively im-portant than ambient and design factors.Nine store ex-pectation dimensions were categorised and the resultdemonstrated that most respondents were concerned onthe social aspect in their expectation of having a satisfy-ing store environment.

Hydrogen-bonded Three-Dimensional Networks Encapsulating One-dimensional Covalent Chains: [Cu(3-ampy)(H_2O)_4](SO_4)·(H_2O) (3-ampy = 3-Aminopyridine)

A three-dimensional complex [Cu（3-ampy）（HEO）4]（SO4）·（H2O） （3-ampy = 3-amino- pyridine） has been synthesized. Crystallographic data： C5H16CuN2O9S, Mr = 343.80, triclinic, space group P1, a = 7.675（2）, b = 8.225（3）, c = 10.845（3）A, α= 86.996（4）, β = 76.292（4）, γ= 68.890（4）°, V = 620.0（3）A^3, Z = 2, Dc = 1.841 g/cm^3, F（000） = 354 and μ = 1.971 mm^-1. The structure was refined to R = 0.0269 and wR = 0.0659 for 1838 observed reflections （I 〉 2a（/））. The structure consists of [Cu（3-ampy）（H2O）4]^2＋ cations, SO4^2- anions and lattice water molecules. 3-Ampy acting as a bidentate bridging ligand generates a 1D covalent chain. A supramolecular 2D framework is formed through π-π stacking of pyridine rings. The lattice water molecules and SO4^2- anions are located between the adjacent 2D frameworks. The hydrogen bonding interactions from lattice water molecules and SO4^2- anions to coordinate water extend the 2D framework into a 3D network.

Synthesis and Crystal Structure of an Infinite 1D Zigzag Chain Compound (dimbH^+)(ClO_4^-) and Its Comparison with (dimb)2H_2O (dimb = 1,3-Di(imidazol-1-ylmethyl)-5-methylbenzene)

A new imidazolium compound, C15H17N4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with a = 8.182(2), b = 12.874(3), c = 15.611(4) ? V = 1644.4(7) 3, Dc = 1.425 g/cm3, Z = 4, Mr = 352.78, m(MoKa) = 0.944 mm-1, F(000) = 736, S = 1.036, the final R = 0.0521 and wR = 0.1187 for 1128 observed reflections (I > 2s(I)). An infinite one-dimensional zigzag chain is formed by NH…N hydrogen bonding interactions between the imidazolium salt cations.

Novel Cascade Refrigeration Cycle for Cold Supply Chain of COVID-19 Vaccines at Ultra-Low Temperature -80°C Using Ethane (R170) Based Hydrocarbon Pair

Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80°C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.

基于RBF-PID的无障碍升降平台调速控制策略

为了提高无障碍升降平台的调速精度,提出一种基于RBF神经网络的PID自学习控制策略。建立了电机调速系统的传递函数模型,采用牛顿-欧拉法建立了圆环链传动的动力学模型,在此基础上,设计了一种基于RBF神经网络PID控制器的无障碍升降平台调速控制策略。基于Matlab/Simulink的仿真结果表明,在升降平台空载的运行状态下,RBF神经网络PID控制的跟踪性能相对于传统PID控制而言,最大跟踪误差下降了67.34%,并且优化后的RBF神经网络PID克服了传统PID不能自适应整定参数的缺点,能够实现快速收敛。

程潮矿业公司链篦机-回转窑-环冷机系统平衡考察与分析

为了了解程潮矿业公司球团厂链篦机-回转窑-环冷机系统三大主机的热工状态,对系统的物料、风量及热量平衡进行了考察与分析,并为优化现场热工制度提出了合理建议。结果表明,链篦机机漏风率为10.86%,链篦机、回转窑和环冷机热损失率分别为5.38%、12.09%和1.87%,需针对风箱和烟罩密封性进行检修,降低漏风率和热损失,对回转窑内耐火砖进行实时监测,定期更换破损耐火砖,降低窑内散热。