On subspaces of non-commutative Lp-spaces

We study some structural aspects of the subspaces of the non-commutative (Haagerup) L_p-spaces associated with a general (non-necessarily semi-finite) von Neumann algebra . If a subspace X of contains uniformly the spaces ?_pⁿ, n?1, it contains an almost isometric, almost 1-complemented copy of ?_p. If X contains uniformly the finite dimensional Schatten classes S_pⁿ, it contains their ?_p-direct sum too. We obtain a version of the classical Kadec-Pe?czyński dichotomy theorem for L_p-spaces, p?2. We also give operator space versions of these results. The proofs are based on previous structural results on the ultrapowers of , together with a careful analysis of the elements of an ultrapower which are disjoint from the subspace . These techniques permit to recover a recent result of N. Randrianantoanina concerning a subsequence splitting lemma for the general non-commutative L_p spaces. Various notions of p-equiintegrability are studied (one of which is equivalent to Randrianantoanina's one) and some results obtained by Haagerup, Rosenthal and Sukochev for L_p-spaces based on finite von Neumann algebras concerning subspaces of containing ?_p are extended to the general case.     

Noncommutative maximal ergodic theorems

This paper is devoted to the study of various maximal ergodic theorems in noncommutative -spaces. In particular, we prove the noncommutative analogue of the classical Dunford-Schwartz maximal ergodic inequality for positive contractions on and the analogue of Stein's maximal inequality for symmetric positive contractions. We also obtain the corresponding individual ergodic theorems. We apply these results to a family of natural examples which frequently appear in von Neumann algebra theory and in quantum probability.

     

放电等离子体技术在固态生物质聚合中的应用

本文介绍了高电压放电等离子体技术在生物质高分子聚合中的应用及机理,提出了把等离子体聚合技术应用于固体高分子生物质中,拓宽了等离子体聚合的应用范围及聚合产物的形态,讨论了在实现生物质等离子体聚合中,固体高分子原料聚合需要解决的问题,并就等离子体聚合在这方面的应用进展状况进行了扼要介绍,同时对其发展前景进行了展望。     

Calcul fonctionnel et fonctions carrées dans les espaces Lp non commutatifs

We introduce suitable square functions for sectorial operators on noncommutative L^p-spaces, and we investigate their relationships with H^∞ functional calculus. To cite this article: M. Junge et al., C. R. Acad. Sci. Paris, Ser. I 337 (2003).     

Noncommutative Burkholder/Rosenthal inequalities II: Applications

We show norm estimates for the sum of independent random variables in noncommutative L _p -spaces for 1 < p < ∞, following our previous work. These estimates generalize the classical Rosenthal inequality in the commutative case. As applications, we derive an equivalence for the p-norm of the singular values of a random matrix with independent entries, and characterize those symmetric subspaces and unitary ideals which can be realized as subspaces of a noncommutative L _p for 2 < p < ∞. The first author is partially supported by the National Science Foundation DMS-0301116. The second author is partially supported by the Agence Nationale de Recherche 06-BLAN-0015.     

高效液相色谱-串联质谱法同时测定蜂王浆中7种高风险农药残留

建立了高效液相色谱-串联质谱（HPLC-MS/MS）同时测定蜂王浆中氟胺氰菊酯、三唑醇、蝇毒磷、吡氟乙草灵、多菌灵、乙基硫菌灵和甲基硫菌灵7种高风险农药残留的分析方法。样品在碱性条件下经乙腈提取,无水硫酸钠脱水后,采用HLB固相萃取小柱富集净化。采用Venusil MP C18色谱柱分离,以0.5 mmol/L乙酸铵水溶液（含0.1%（v/v）甲酸）-甲醇（含0.1%（v/v）甲酸）为流动相,梯度洗脱。在电喷雾离子（ESI）源、正离子模式和多反应监测（MRM）模式下采集数据,内标法定量。结果表明,7种高风险农药在5~100 μg/kg范围内线性关系良好,相关系数（r²）为0.9921~0.9996;方法的检出限和定量限分别为0.5~2.0 μg/kg和1.0~5.0 μg/kg。在高、中、低3个添加水平下7种农药的加标回收率为80.5%~101.3%,相对标准偏差（RSD）为3.6%~9.4%。该法操作简单,灵敏度高,准确可靠,能够满足出口蜂王浆农残限量检测的要求。     

Some results related to interpolation on hardy spaces of regular martingales

Let (Ω,F, P) be a probability space and {F _n}_n≥0 a regular increasing sequence of sub-σ-fields ofF. LetH ₁(Ω) be the usual Hardy space ofF _n-martingales. We show that the couple (H ₁(Ω),L _∞(Ω)) is a partial retract of (L ₁(Ω),L _∞(Ω)). It is also proved that (L _p(Ω),BMO(Ω)) is a partial retract of (L _p(Ω),L _∞(Ω)) for all 1<p<∞.     

Convexités uniformes et inégalités de martingales

Sans résumé     

Stability and Crystallinity of Sodium Poly(Heptazine Imide) in Photocatalysis

Poly(heptazine imide) (PHI) salts, as crystalline carbon nitrides, exhibit high photocatalytic activity and are being extensively researched, but its photochemical instability has not drawn researchers’ attention yet. Herein, sodium PHI (PHI−Na) ultrathin nanosheets with increased crystallinity, synthesized by enhancing contact of melamine with NaCl functioning as a structure-induction agent and hard template, exhibits improved photocatalytic hydrogen evolution activity, but low photochemical stability, owing to Na⁺ loss in the photocatalytic process, which, interestingly, can be enhanced by the common ion effect, e.g., addition of NaCl that is also able to remarkably increase the photoactivity with the apparent quantum yield at 420 nm reaching 41.5 %. This work aims at attracting research peers’ attention to photochemical instability of PHI salts and provides a way to enhance their crystallinity.     

高温非平衡流动中的氧分子振动态精细分析

高超声速流动在头激波压缩后常处于高 温条件下的热化学非平衡状态. 本文采用态-态方法和双温度模型计算分析了一维正激波后和高超声速钝体绕流驻点线上的氧气热化学非平衡流动. 态-态方法将氧气的每个振动能级当成独立的组分,通过耦合 Euler 方程或驻点线上的降维 Navier-Stokes 方程,数值求解得 到了高温流动中的精细热化学非平衡状态. 而双温度模型假设氧气的振动能级服从 Boltzmann 分布,通过求解振动能方程得到振动温度. 一维正激波后热化学松弛过程的计算结果表明,态-态计算预测的温度分布和氧原子浓度分布较好地吻合了文 献中的实验结果,而经典的双温度模型的预测结果误差较大,且不同双温度模型的计算结果比较发散. 态-态方法详细地给出了所有振动能级的变化过程. 无论是正激波还是脱体激波后的流场,都是高振动能级首先得到激发;但是数密度大的低振动能级先达到热平衡,而高能级 分子要经过很长距离后才能达到热平衡. 在驻点附近,复合反应生成的氧气分子处于高振动能级,导致高振动能级分子数密度显著高于平衡分布. 计算还发现,经典双温度模型的离解反应速率明显偏离态-态计算结果,无法准确体现振动离解耦合效应对离解反应 速率的影响,但是 Park 双温度模型将离解失去的振动能取为 0.3$\sim 高超声速流动在头激波压缩后常处于高 温条件下的热化学非平衡状态. 本文采用态-态方法和双温度模型计算分析了一维正激波后和高超声速钝体绕流驻点线上的氧气热化学非平衡流动. 态-态方法将氧气的每个振动能级当成独立的组分,通过耦合 Euler 方程或驻点线上的降维 Navier-Stokes 方程,数值求解得 到了高温流动中的精细热化学非平衡状态. 而双温度模型假设氧气的振动能级服从 Boltzmann 分布,通过求解振动能方程得到振动温度. 一维正激波后热化学松弛过程的计算结果表明,态-态计算预测的温度分布和氧原子浓度分布较好地吻合了文 献中的实验结果,而经典的双温度模型的预测结果误差较大,且不同双温度模型的计算结果比较发散. 态-态方法详细地给出了所有振动能级的变化过程. 无论是正激波还是脱体激波后的流场,都是高振动能级首先得到激发;但是数密度大的低振动能级先达到热平衡,而高能级 分子要经过很长距离后才能达到热平衡. 在驻点附近,复合反应生成的氧气分子处于高振动能级,导致高振动能级分子数密度显著高于平衡分布. 计算还发现,经典双温度模型的离解反应速率明显偏离态-态计算结果,无法准确体现振动离解耦合效应对离解反应 速率的影响,但是 Park 双温度模型将离解失去的振动能取为 0.3$\sim $0.5 倍分子离解能是比较合理的.