关于算术数列中三个或多个素数的和

作为圆法的一个应用,考虑算术数列中的素变数方程P1＋P2＋…＋Pk=N,Pi≡gi（modh）,j=1,2,…,k,∑1≤j≤kgj≡N（modh）,k≥3,给出了方程在大模情况下解的个数的渐近公式,即设≥3,H=sup{β：L（β＋iγ,x）=0},ε〉0,1≤h≤N^δ,0〈δ〈1,则∑p1＋p2＋…＋pk=N/pj≤N,pj≡gj（modu）,1≤j≤k（logp1）（logp2）…（loghk）=1/（k-1）!Nk-1y（k,N）＋O（Nk-2＋H＋c）＋O（Nηk＋c）＋O（Nk-2＋λ＋c）,其中η3=5/9,η4=14/5和ηk=0（k≥5）,λ={β^-,若L函数存在例外零点β^-,/0,若L函数不存在例外零点,y（k,N）=h/φ（h）^k∏p×h,p×N（1＋（-1）^k＋1/（p-1）^k）∏p×h,p｜N（1＋（-1）^k/（p-1）^k-1）.     

正整数方幂和的多项式表示

研究正整数方幂和Sk(n)=n∑a=1ak的多项式表示.结合初等数论及组合的方法,证明了正整数方幂和S2k-1(n)可展开为包含因子n(n+1)且关于n(n+1)的k阶有理多项式;S2k(n)可展n开为包含因子n(n+1)(2n+1)且关于n(n+1)的k阶有理多项式,并且给出Sk(n)=n∑a=1ak展开成多项式后系数的确切计算公式.     

关于多组组合数的一个渐近公式

对于给定的自然数n和k,若把kn个不同的元素分成k组,每组都有n个不同的元素,这样分组的种数为Ckn^（k）=（（kn）!/（n!）^k.研究了这种多组组合数Ckn^（k）在素因数个数函数（包括重数在内）上的值分布性质,并得到了一个有趣的渐近公式.     

构造（2＋1）维扰动Boussinesq方程的近似守恒律

利用近似Noether-type对称算子构造了具有扰动项的（2＋1）维Boussinesq方程的近似守恒向量和近似守恒律,在（2＋1）维Boussinesq方程允许的拉格朗日函数的情况下,利用近似Noether法研究了该方程的守恒律,给出了（2＋1）维扰动Boussinesq方程的近似Noether对称算子、近似守恒向量以及近似守恒律．     

复式纤维分离机气动阀电路改进

本设备主要用于分离废纸浆中的轻、重杂物．并对来自水力碎浆机的浆料进行二次碎解。浆料切向进入槽体，在叶轮作用下加速，在槽体内产生涡流，涡流产生的向心力使轻杂物聚集在涡流的中心而重杂物则被甩向槽壁，重杂物与部分浆料一起经重杂物排放管进入重杂物除渣器。经除渣器除去重杂物后的浆料重新送回进料管，收集在除渣器杂物槽中的重杂物通过气动问定时排放，由V1和V2两个阀门控制。如图1。自设备投入运行以来，效果十分显著，大大提高了纸张的质量。但是，有时V1及V2阀产生误动作，使浆料流失。原因是（V1、V2阎置于自动位置）当V…     

ALCOPRINT—RB（7860）增稠剂在活性染料印花中的应用

纯棉活性染料印花是染料印花的重要工艺之一。长期以来，活性染料印花的原糊都以海藻酸钠为主要糊料，海藻酸钠分子中含有大量的阴离子羧基，对重金属离子（Ca∧2 、Mg∧2 、Fe∧2 等）会产生沉淀凝胶的作用，破坏色浆的稳定性能，影响染色牢度。与阴离子化合物多存在分子间的静电斥力（活性染料多属于阴荷性），防止了活性染料与海藻酸钠的结合，促进了染料的上染。由海藻酸钠原糊制得的色浆渗透性、吸湿性均很好，而给色量却低，尤其是在圆网印制中更低，均匀性也相对较差。     

二维液相色谱法测定烧烤肉制品中苯并（a）芘

烧烤肉制品由于富含动物油脂,在炭火高温烧烤熟制品过程中,容易出现苯并（a）芘超标问题,具有较高安全隐患。建立二维液相色谱仪检测烧烤肉制品中苯并（a）芘的方法。第1维为分离、富集柱,采用Inertsil ODS柱（4.6 mm×150 mm,5 μm）,流动相为乙腈-水（85∶15,V/V）,流速1.0 mL/min,可以实现500 μL样品中目标物苯并（a）芘的富集与分离;第2维采用ChromSpher Pi柱（3.0 mm×80 mm,5 μm）,流动相为异丙醇-乙腈（60∶40,V/V）,流速1.2 mL/min,可以有效分离、测定样品中的苯并（a）芘。结果表明：烧烤肉制品中苯并（a）芘在1.0～20.0 ng/mL范围内呈线性关系,其线性回归方程为y=1.847 1x－0.103 3（r=0.999）,检出限为0.08 μg/kg,在1.00、3.00、5.00、10.00 μg/kg加标水平下,加标回收率为97.1%～105.2%,相对标准偏差为1.55%～2.77%。     

Smarandache Ceil函数的均值

Smarandache函数的相关性质是初等数论和解析数论研究的一个重要问题.本文利用初等方法给出了Smarandache Ceil函数Sk(n)与n的k次补数函数ak(n)之间的关系式(Sk(n))k=ak(n)·n,再利用解析方法给出了Sk(n)一个渐近公式∑n≤xSk(n)=ζ(2k-1)/2x2∏p(1-1/p2+p-1/p2k-1+p2k-2)+O(x3/2+ε).     

效应代数中的 N-值伪补

在效应代数中引入了 R-覆盖、N-覆盖以及 N-值伪补的概念并研究了它们的性质，讨论了效应代数中的伪补和正交补的关系，证明了若 E是具有 N-值伪补关系的格值效应代数，则 E具有 N-覆盖性质，并且橙 a ，b∈ E ，γ（a∧b）＝γa∧γb 。     

钐-5-磺基水杨酸配合物的合成、晶体结构及光学性能

采用水溶剂热法合成出钐配合物Sm（SSA）（H2O）2·H2O,并通过元素分析、红外光谱、热重分析对其结构进行表征,利用紫外及荧光分光光度计研究配合物的光学性能,用X-射线单晶衍射仪测定配合物的晶体结构．结果表明,晶体属于单斜晶系,空间群为P2（1）／n;晶胞参数a=0．88844（16）nm,b=0．89254（16）nm,c=1．4366（3）nm,a=90．00°,β-100．810（2）°,）,γ=90．00°,Z=4,V=1．1190（3）nm^3（CCDCNo．：875346）．中心金属离子Sm与周围的8个氧原子形成了四方反棱柱体的几何构型．     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the