无周期光学超晶格中误差函数研究（英文）

利用非线性共轭梯度算法设计了无周期光学超晶格结构,研究了文献[12]提出的误差函数在该结构中的适用性.研究结果表明:误差函数能够很好地适用于无周期光学超晶格结构,且该结构比文献[12]中所用的非周期光学超晶格更具有一般性;当u′_2(x_n)和n保持很好的线性关系时,无周期光学超晶格结构中计算所得的误差函数曲线与文献[12]中的误差函数曲线几乎是重合的,说明了在无周期光学超晶格中达到了很好的准相位匹配.通过在样品中引入随机误差进一步研究了相位失配情况下误差函数在无周期光学超晶格结构中的适用性,结果表明:相位失配时无周期光学超晶格结构中计算所得的误差函数曲线与标准曲线是有偏离的,且相位失配程度越大,偏离也越大;对于一些误差函数曲线与标准曲线偏离不大的情况,误差函数仍可近似地用来估计无泵浦损耗近似的适用范围.

无周期光学超晶格中耦合三次谐波转换效率的提高

利用非线性共轭梯度算法(NCG)设计了无周期光学超晶格(NOS),在该结构中实现了高转换效率的耦合三次谐波(CTHG)。相对于传统的模拟退火算法(SA)所设计的非周期光学超晶格(AOS),无论单波长还是多波长的CTHG,利用NCG算法所设计的NOS结构可以得到更高的转换效率。这是因为在无周期光学超晶格结构中每层畴的宽度的选取是任意的,通过NCG算法对每层畴宽度进行优化,可以达到更好的准相位匹配(QPM)。计算了转换效率随光波传播距离的变化情况,结果表明转换效率随光波传播距离的增加而增大,这说明每层畴对转换效率的贡献是积极的,所设计的样品达到了准相位匹配。

摆动行波的时空结构

基于流体力学方程组,对长高比Γ=30腔体内混合流体对流中摆动行波的时空结构进行了数值模拟。结果发现:当分离比Ψ=-0.6,-0.4时,在摆动行波存在的下临界附近,摆动行波的对流滚动有消失也有产生,对流平均波数在周期内变化;在摆动行波存在的上临界附近,摆动行波的对流滚动既无消失也无产生,对流平均波数保持为常数。随着相对瑞利数r的增加,对流滚动的摆动幅度和摆动周期明显减小。当分离比Ψ=-0.6时,摆动行波是准周期的;当分离比Ψ=-0.4时,摆动行波是周期的;当分离比Ψ=-0.2时,在摆动行波存在的下临界附近,观察到了一种沿着行波的对称轴线两侧发生对称的摆动行波的新型对流结构。在摆动行波存在的上临界附近,摆动行波是无周期的。随着分离比负值减小,摆动行波存在的上、下限下移,摆动行波存在的稳定区间Δr减小。

局部稠密的交换半群与无限闭子半群的关系

利用拓扑半群的性质讨论了无限交换拓扑半群与无限闭子半群的关系,并推广了有关结果.

Infinitely many periodic solutions for second-order Hamiltonian systems

The existence of high energy periodic solutions for the second-order Hamiltonian system -ü（t）＋A（t）u（t）=▽F（t,u（t）） with convex and concave nonlinearities is studied, where F（t, u） = F1（t,u）＋F2（t,u）. Under the condition that F is an even functional, infinitely many solutions for it are obtained by the variant fountain theorem. The result is a complement for some known ones in the critical point theory.

Roux-en-Y reconstruction does not require gastric decompression after radical distal gastrectomy

AIM: To determine whether routine nasogastric (NG) decompression benefitted patients undergoing radical gastric surgery. METHODS: Between January 1998 and December 2008, 519 patients who underwent distal gastrectomy for gastric cancer were retrospectively divided into 2 time-period cohorts; those treated with Billroth Ⅱ (BⅡ) reconstruction in the first 6 years and those with Roux-en-Y (RY) reconstruction in the last 5 years. In the latter group, the patients were further divided into 2 subgroups; with and without nasogastric decompression.RESULTS: Postoperatively, there were no significant differences in the number of anastomotic leaks between the 3 groups. In the tubeless RY group, time to semiliquid diet was significantly shorter than in the other 2 groups (4.4 d ± 1.4 d vs 7.2 d ± 1.3 d and 5.9 d ± 1.2 d, P = 0.005). The length of postoperative stay was significantly increased in patients with BⅡ reconstruction compared with patients with RY reconstruction with/without NG decompression (15.4 d ± 4.3 d in BⅡ group vs 12.6 d ± 3.1 d in decompressed RY and 11.4 d ± 3.4 d in the tubeless RY group, P = 0.035). The postoperative pneumonia rate was lowest in the tubeless group and highest in the BⅡ group (1.4% vs 4.6%, P = 0.01). Severe sore throat was noted in 59 (20.7%) members of the BⅡ group, 18 (17.4%) members of the decompressed RY group and 6 (4.2%) members of the tubeless RY group. Fewer patients in the tubeless group complained of severe sore throat (P = 0.001). CONCLUSION: This study provides support for abandoning routine NG decompression in patients undergoing subtotal gastrectomy with Roux-en-Y gastrojejunostomy.

Statistical Properties and Confidence Limits about the Mean Time between the Failures (MTBF) in Failure-free Period Life Test (FFPLT)

On the basis of strict mathematical description about Failure_Free Period Life Test (FFPLT), the statistical properties of the tests and optimal confidence limit of the parameter are discussed in detail and corresponding calculating formulae are found out.

Paleoproductivity evolution in the West Philippine Sea during the last 700 ka

In order to reconstruct the paleoproductivity evolution history of the West Philippine Sea during the last 700 ka, the vertical gradient of Δδ13C in dissolved inorganic carbon Δδ13C between those of foraminifera Pulleniatina obliquiloculata and Cibicidoides wuellerstorfi） and planktonic foraminiferal assemblages were analysed in piston Core MD06-3047 retrieved from the Benham Rise （east of the Luzon Island）. Paleoproductivity evolution in the West Philippine Sea during the last 700 ka is closely related to glacial-interglacial cycles and precession-controlled insolation. Controlling factors ofpaleoproductivity could have been both thermocline fluctuations related with ENSO-Iike processes and eolian input associated with East Asian winter monsoon, and the former could have been the primary factor. A higher productivity and a shallower thermocline coeval with the occurrence of low CO2 concentrations in the EPICA Dome C ice core might indicate that biological export production in the low-latitude could act as a significant sink in the global carbon cycle, and modify atmospheric CO2 concentrations. Spectral analysis further reveals that the paleoproductivity is mainly controlled by thermocline fluctuations subjected to ENSO processes responding to processional variability of insolation. High coherences in eccentricity, obliquity and precession periods fiuther revealing the close link between thermocline fluctuations, paleoproductivity and atmospheric CO2 levels.

On a max-type difference equation

This paper studies the asymptotic behavior of solutions of the difference equation X（n＋1）=max{C1/Xn,C2/X（n-1）},n=0,1,…,where the parameters C1, C2 and the initial conditions x（-1）, xo are nonzero real numbers. More precisely, it has been proved that： （1） if Ct 〈 0 and C2 〉 0, then every solution of the equation is eventually periodic; （2） if Ct 〈 0 and C2 〈 0, then every solution of the equation is unbounded when C1≠P C2 or is eventually periodic when C1 = C2.

Turning Industrial Residues into Resources： An Environmental Impact Assessment of Goethite Valorization

Goethite is a metals-rich residue that occurs during zinc production. The feasibility of metal recovery from goethite has been demonstrated, but is not economically viable on an industrial scale. Therefore, goethite is landfilled with considerable economic costs and environmental risks. The goal of this study is to evaluate the environmental performance of a new valorization strategy for goethite residues from zinc production, with the aims of： ① recovering the valuable zinc contained in the goethite and ② avoiding the landfilling of goethite by producing a clean byproduct. The presented goethite valoriza- tion strategy consists of a sequence of two processes： ① plasma fuming and ② inorganic polymerization of the fumed slag. Plasma fuming recovers the valuable metals by fuming the goethite. The metals-flee fumed slag undergoes a process of inorganic polymerization to form inorganic polymers, that can be used as a novel building material, as an alternative to ordinary Portland cement （OPC）-based concrete. Life- cycle assessment （LCA） is used to compare the environmental performance of the inorganic polymer with the environmental performances of equivalent OPC-based concrete. The LCA results show the tradeoff between the environmental burdens of the fuming process and inorganic polymerization versus the environmental benefits of metal recovery, OPC concrete substitution, and the avoidance of goethite land- filling. The goethite-based inorganic polymers production shows better performances in several environ- mental impact categories, thanks to the avoided landfilling of goethite. However, in other environmental impact categories, such as global warming, the goethite valorization is strongly affected by the high-energy requirements of the plasma-fuming process, which represent the environmental hotspots of the proposed goethite recycling scheme. The key elements toward the sustainability of goethite valorization have been identified, and include the use of a clean electric mix, more effective control of the fumed gas emissions, and a reduced use of fumed slag through increased efficiency of the inorganic polymerization process.

Application of Controlled Hypothermia Radio-frequency Ablation Technique in Otolaryngology

Objective: To explore the application of controlled hypothermia radio-frequency ablation technique in otolaryngology. Methods: Germany Bipolar controlled hypothermia radio-frequency with varying tips was used for obstructive sleep apnea-hyponea syndrome, chronic hypertrophic rhinitis, allergic rhinitis, aural pseudocyst, phymatoid proliferation of tongue root, capillary hemangioma of nose and pharynx. Follow up was made up to six months. Results:All patients had curative effects. Conclusion: Hypothermia radio-frequency ablation technique was used effectively for many diseases in otolaryngology with features of accurate ablation, low complication, reliable effects as well as easyusing. It was a prospective method of micro invasive surgery.

Periodic Solutions of Singular Neutral Differential Systems with Infinite Delay

In this paper,we discuss the periodic solutions of the nonlinear singular neutral differential systems with infinite delay.By using matrix measure and Krasnoselskii＇s fixed point theorem,we obtained the suffcient conditions of the existence of periodic solutions.

Periodic Solutions of Lienard Equations withInfinite Delay

The problem of periodic solutions for Lienard equations with infinite delay x+(?)x+g(t,xt)=p(t)is discussed by using Mawhin's,coincidence degree theory. Some new results on the existence of periodic solutions are derived.

Acyclic edge coloring of planar graphs without adjacent cycles

A proper edge coloring of a graph G is said to be acyclic if there is no bicolored cycle in G.The acyclic edge chromatic number of G,denoted byχ′a(G),is the smallest number of colors in an acyclic edge coloring of G.Let G be a planar graph with maximum degree.In this paper,we show thatχ′a(G)+2,if G has no adjacent i-and j-cycles for any i,j∈{3,4,5},which implies a result of Hou,Liu and Wu(2012);andχ′a(G)+3,if G has no adjacent i-and j-cycles for any i,j∈{3,4,6}.

Existence of Positive Periodic Solutions of Competitor-Competitor-Mutualist Lotka-Volterra Systems with Infinite Delays

In this paper,the authors primarily explore a delayed competitor-competitor-mutualist Lotka-Volterra model,which is a system of differential equation with infinite integral.The authors first study the existence of positive periodic solutions of the model by using the Krasnoselskii's fixed point theorem,and then present an example to illustrate the main results.

Theory of center-focus for a class of higher-degree critical points and infinite points

For the real planar autonomous differential system, the questionsof detection between center and focus, successor function, formal series, central integration, integration factor, focal values, values of singular point and bifurcation of limit cycles for a class of higher-degree critical points and infinite points are expounded.

On a Class of Infinite-Dimensional Hamiltonian Systems with Asymptotically Periodic Nonlinearities

The authors study the existence of homoclinic type solutions for the following system of diffusion equations on R × RN：{atu-xu ＋ b ·▽xu ＋ au ＋ V（t,x）v = Hv（t,x,u,v）,-atv-xv-b·▽xv ＋ av ＋ V（t,x）u = Hu（t,x,u,v）,where z =（u,v）：R × RN → Rm × Rm,a 〉 0,b =（b1,···,bN） is a constant vector and V ∈ C（R × RN,R）,H ∈ C1（R × RN × R2m,R）.Under suitable conditions on V（t,x） and the nonlinearity for H（t,x,z）,at least one non-stationary homoclinic solution with least energy is obtained.

Fine mapping and candidate gene prediction of the photoperiod and thermo-sensitive genic male sterile gene pms1(t) in rice

Pei＇ai64S, an indica sterile variety with photoperiod and thermo-sensitive genic male sterile （PTGMS） genes, has been widely exploited for commercial seed production for ＂two-line＂ hybrid rice in China. One PTGMS gene from Pei＇ai64S, pmsl（t）, was mapped by a strategy of bulked-extreme and recessive-class approach with simple sequence repeat （SSR） and insert and deletion （In-Del） markers. Using linkage analysis for the F2 mapping population consisting of 320 completely male sterile individuals derived from a cross between Pei＇ai64S and 93-11 （indica restorer） lines, the pmsl（t） gene was delimited to the region between the RM21242 （0.2 cM） and YF11 （0.2 cM） markers on the short arm of chromosome 7. The interval containing the pmsl（t） locus, which was co-segregated with RM6776, is a 101.1 kb region based on the Nipponbare rice genome. Fourteen predicted loci were found in this region by the Institute for Genomic Research （TIGR） Genomic Annotation. Based on the function of the locus LOC_Os07g12130 by bioinformatics analysis, it is predicted to encode a protein containing a Myb-like DNA-binding domain, and may process the transcript with thermosensory response. The reverse transcription-polymerase chain reaction （RT-PCR） results revealed that the mRNA levels of LOC_Os07g12130 were altered in different photoperiod and temperature treatments. Thus, the LOC_Os07g12130 locus is the most likely candidate gene for pmsl（t）. These results may facilitate not only using the molecular marker assisted selection of PTGMS genes, but also cloning of the pmsl（t） gene itself.

Pseudo-almost periodic solution for impulsive hematopoiesis model with infinite delays and linear harvesting term

In this paper, a generalized impulsive model of hematopoiesis with infinite delays and linear harvesting term is investigated. The main purpose of this paper is to study the existence, uniqueness and exponential stability of the positive pseudo-almost periodic solutions, which improve and extend some known relevant results. Moreover, an example is given to illustrate the main findings.

Multiple periodic oscillations in the radio light curves of NRAO 530

In this paper,the time series analysis method CLEANest is employed to search for characteristic periodicities in the radio light curves of the blazar NRAO 530 at 4.8,8.0 and 14.5 GHz over a time baseline of three decades.Two prominent periodicities on time scales of ～6.3 and ～9.5 a are identified at all three frequencies,in agreement with previous results derived from different numerical techniques,confirming the multiplicity of the periodicities in NRAO 530.In addition to these two significant periods,there is also evidence of shorter-timescale periodicities of ～5.0,～4.2,～3.4 and ～2.8 a showing lower amplitude in the periodograms.The physical mechanisms responsible for the radio quasi-periodic oscillations and the multiplicity of the periods are discussed.