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991.
8-羟基喹啉纤维分离富集-ICP-AES同时测定多种痕量稀土元素 总被引:1,自引:0,他引:1
8-羟基喹啉纤维分离富集-ICP-AES同时测定多种痕量稀土元素郭伊荇,刘春明,赵晓亮,王为玲(东北师范大学测试中心,长春,130024)关键词8-羟基喹啉纤维滤纸片,稀土元素,电感耦合等离子体原子发射光谱地球化学样品中稀土元素的测定主要采用离子交换... 相似文献
992.
THEAPPLICATIONOFTHEVARIATIONALPRINCIPLEINTHECONSTRAINEDCONTROLSYSTEMDengZi-chen(邓子辰)(NorthwesternPolytechnicalUniversityXi'an... 相似文献
993.
Wojciech Koch Wirginia Kukula-Koch Marcin Czop Tomasz Baj Janusz Kocki Piotr Bawiec Roser Olives Casasnovas Anna Gowniak-Lipa Kazimierz Gowniak 《Molecules (Basel, Switzerland)》2021,26(19)
A comprehensive approach to the mineral composition of black teas of different origins was studied using the Flame Atomic Absorption Spectrometry (FAAS) method, supported by chemometric tools including Principal Component Analysis PCA) and Classification and Regression Trees (CART). Significant differences between the teas from seven countries (Japan, Nepal, Kenya, Iran, Sri Lanka, India, and China) were shown. K was the main element determined in all teas, with an average concentration of 11,649 mg/kg, followed by Ca, Mg and Mn. In general, regarding all investigated black teas, the element content was ranked in the following order: K > Ca > Mg > Mn > Fe > Na > Zn > Cu. The applied chemometric methods allowed us to recognize black tea clusters based on their mineral composition and place of cultivation, and allowed us to find correlations between particular elements in black teas. The performed analyses revealed interesting correlations between the concentration of various elements in black teas: K was negatively correlated with Na, Fe, Mn and Cu; K was positively correlated with the content of Ca and Mg. Significant positive correlations between Mn and Fe and Mn and Zn in the studied black tea samples were also revealed. It was shown that mineral composition may be a significant factor regarding the origin of the black tea, not only considering the country, but also the region or province. 相似文献
994.
本文把三值闭运算拓广而引人三值符合运算,并提出了一种TTL三值“符合非”门的电路设计 相似文献
995.
谢敦礼 《浙江大学学报(理学版)》1985,12(3):319-322
Singer,I.给出了C[a,b]和 L~p[a,b](1≤p< ∞)上线性子空间G的点g_0是点x的最佳逼近元的特征,本文进一步讨论在Orlicz空间上最佳逼近元的特征.文中的术语和记号见[1],[2].设M(·)和N(·)是满足△_2-条件的,互余的N-函数,相应的导数p(·)连续且严格单调增加.这时,M(·)和N(·)的图形不含直线段,所以,根据吴从炘的定理,以Luxemburg范数||·||(m)为范数的Orlicz空间L_(M)~*[a,b]是严格凸的,L_N~*[a,b]也是严格凸的.此外,易见在上述条件下,L_(M)~*的对偶是L_N~*且是自反的,因此,L_(M)~*也是光滑的. 相似文献
996.
O. A. Bondarenko A. A. Korneev Yu. N. Onishchuk A. V. Berezhnoy P. B. Aryasov D. Antonyuk A. V. Dmitrienko 《Radiation measurements》1999,30(6):709-714
Object “Shelter” (known world-wide as the Sarcophagus) is a source of very high radiological and nuclear hazard. Transfer of the Sarcophagus into an ecologically safe site is a task not only for Ukraine but also for the world community. A composite approach to maintenance of radiation and nuclear safety of the Sarcophagus applying spectrometric methods using solid state nuclear track detectors (SSNTD) is suggested in this paper. The aspects are: (1) monitoring of transuranium element inhalation intake to a human body of nuclear workers; (2) neutron flux evaluation in some premises of the Sarcophagus; (3) fuel hot particle detection in air of working zones; (4) radon and thoron simultaneous measurements. 相似文献
997.
998.
GENERALIZED DIFFERENCE METHODS ON ARBITRARY QUADRILATERAL NETWORKS 总被引:14,自引:0,他引:14
1.IntroductionConsidertheboundaryvalueproblemofthePoissonequationwherefiisaconvexpolygonregon;r~OfftheboundaryofOandf(x,y)aknownfunctiononfi.Thegeneralizeddifferencemethodsonquadrilateralnetworksforellipticequationsareproposedin[11],'wheretheconverge... 相似文献
999.
We consider a GI/G/1 queue in which the service time distribution and/or the interarrival time distribution has a heavy tail,
i.e., a tail behaviour like t
−ν with 1 < ν ⩽ 2 , so that the mean is finite but the variance is infinite. We prove a heavy-traffic limit theorem for the
distribution of the stationary actual waiting time W. If the tail of the service time distribution is heavier than that of the interarrival time distribution, and the traffic
load a → 1, then W, multiplied by an appropriate ‘coefficient of contraction’ that is a function of a, converges in distribution to the Kovalenko distribution. If the tail of the interarrival time distribution is heavier than
that of the service time distribution, and the traffic load a → 1, then W, multiplied by another appropriate ‘coefficient of contraction’ that is a function of a, converges in distribution to the negative exponential distribution.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
1000.
Exceptional Families of Elements for Continuous Functions: Some Applications to Complementarity Theory 总被引:4,自引:0,他引:4
Using the topological degree and the concept of exceptional family of elements for a continuous function, we prove a very general existence theorem for the nonlinear complementarity problem. This result is an alternative theorem. A generalization of Karamardian's condition and the asymptotic monotonicity are also introduced. Several applications of the main results are presented. 相似文献