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排序方式: 共有182条查询结果,搜索用时 15 毫秒
1.
Let p ∈ [1, ∞), q ∈ [1, ∞), α∈ R, and s be a non-negative integer. Inspired by the space JNp introduced by John and Nirenberg(1961) and the space B introduced by Bourgain et al.(2015), we introduce a special John-Nirenberg-Campanato space JNcon(p,q,s) over Rn or a given cube of R;with finite side length via congruent subcubes, which are of some amalgam features. The limit space of such spaces as p →∞ is just the Campanato space which coincides with the space BMO(the space of functions with bounded mean oscillations)when α = 0. Moreover, a vanishing subspace of this new space is introduced, and its equivalent characterization is established as well, which is a counterpart of the known characterization for the classical space VMO(the space of functions with vanishing mean oscillations) over Rn or a given cube of Rn with finite side length.Furthermore, some VMO-H1-BMO-type results for this new space are also obtained, which are based on the aforementioned vanishing subspaces and the Hardy-type space defined via congruent cubes in this article. The geometrical properties of both the Euclidean space via its dyadic system and congruent cubes play a key role in the proofs of all these results. 相似文献
2.
Boundedness of commutators on homogeneous Herz spaces 总被引:9,自引:0,他引:9
The boundedness on homogeneous Herz spaces is established for a large class of linear commutators generated by BMO(R
n
) functions and linear operators of rough kernels which include the Calderón-Zygmund operators and the Ricci-Stein oRfiUatory
singular integrals with rough kernels.
Project supponed in pan by the National h’atural Science Foundation of China (Grant No. 19131080) and the NEDF of China. 相似文献
3.
关于多线性振荡奇异积分在加权Hardy-型空间上的一致估计 总被引:1,自引:0,他引:1
本文对一类具有光滑位相函数的多线性振荡奇异积分算子建立了一致的加权(H^1(R^n),L^1(R^n))估计及一致的加权(HKp(R^n),Kp(R^n)估计。 相似文献
4.
杨大春 《中国科学A辑(英文版)》2003,46(5)
This paper introduces the fractional Sobolev spaces on spaces of homogeneous type,includingmetric spaces and fractals. These Sobolev spaces include the well-known Hajfasz-Sobolev spaces as specialmodels.The author establishes varions chaaracterizations of(sharp)maximal functions for these spaces.Asapplications,the author identifies the fractional Sobolev spaces with some Lipscitz-type spaces.Moreover;some embedding theorems are also given. 相似文献
5.
A series of nine porphyrin analogues have been synthesized using the "3 + 1" variant on the MacDonald condensation. Tripyrrane-type systems with a centrally unsubstituted pyrrole, furan, or thiophene ring were prepared using conventional methods, and these were condensed with indene-1,3-dicarbaldehyde, 5-formylsalicylaldehyde, or 3-hydroxy-2,6-pyridinedicarbaldehyde in the presence of TFA to generate benzocarba-, oxybenzi-, and oxypyriporphyrins, respectively. The furan-containing analogues proved to be highly basic and could only be isolated as the corresponding hydrochloride salts. All nine analogue systems showed porphyrin-like UV-vis spectra with one or two Soret absorptions near 400 nm and a series of weaker bands at longer wavelengths. These systems also showed large diatropic ring currents by proton NMR spectroscopy that were comparable to true porphyrins. In the presence of trace amounts of TFA, benzocarbaporphyrin 12 formed a monocation, and in 50% TFA a C-protonated dication was generated. The 23-oxacarbaporphyrin 14 gave a monocation in chloroform, although the free base was generated in 5% Et(3)N-chloroform. In 50% TFA-CHCl(3), 14 afforded a mixture of mono- and diprotonated species. Thiacarbaporphyrin 15 also formed a monocation in the presence of TFA, but C-protonation was relatively disfavored for this system. Nonetheless, in the presence of TFA-d, 12, 14, and 15 all showed rapid exchange of the internal NH and CH protons. Carbaporphyrin 12 also showed slow exchange at the meso-positions, but this process was not observed for its heteroanalogues 14 and 15. Protonation studies were also conducted for oxybenziporphyrins and oxypyriporphyrins 16-21. Oxacarbaporphyrin 14 was shown to be a superior organometallic ligand and afforded good yields of the related nickel(II) and palladium(II) derivatives under mild conditions. A low yield of the platinum(II) complex could also be isolated. All three complexes retained their aromatic character, although the Pd(II) derivative appeared to possess a slightly larger diatropic ring current. The palladium(II) complex 27 was further characterized by X-ray crystallography. The macrocyclic core was shown to be highly planar where the dihedral angles of the component pyrrole, furan and indene rings relative to the mean [18]annulene plane were all =2.1 degrees. 相似文献
6.
Dachun Yao 《Analytica chimica acta》2003,478(1):23-30
A new detection system based on microdialysis sampling and chemiluminescence (CL) reaction was developed for in vivo monitoring of uric acid (UA) with high sensitivity, selectivity and accuracy. The uric acid is indirectly monitored by CL detection of enzymatic reaction product formation (H2O2), catalyzed by Uricase. A microprobe was modified and coated with immobilized enzyme through a Streptavidin-biotin mediated linker by using a chitosan support membrane, polyurethane trapped ferrocene film is employed to protect the probe surface and diminish the interference from reductant molecules, which often are present in the blood (e.g. ascorbic acid). The earlier mentioned probe and the constructed sensor can detect uric acid in the range of 0.01-1 mM with detection limit (3σ) of 5 μM. Finally, the system is used to monitor uric acid (UA) variation through an acute myocardial infarction (AMI) model. Following AMI-induced oxidative stress, the UA level decreases continuously, thus suggesting that UA plays a protective role as a substitute antioxidant. Furthermore, the in vivo monitoring results show good agreement with those obtained by a standard method, and the procedure is recommended for in vivo and real time monitoring of UA. In addition, the proposed method can be more accurate since the UA may be potentially oxidized by in vitro exposure to oxygen in the presence of a catalyst. 相似文献
7.
神经生长因子的化学发光标记与检测 总被引:1,自引:0,他引:1
以辣根过氧化物酶(HRP)和吖啶酯(AE)为化学发光标记试剂分别标记神经生长因子(NGF)单克隆抗体,经分离纯化制成标记抗体(HRP-Ab,AE-Ab),采用化学发光免疫分析法(CLIA)对NGF进行检测,其检出限为0.5ng/mL,线性范围为2~128ng/mL.10例样本分别用CLIA和RIA进行检测,其结果无显著性差异. 相似文献
8.
The central Campanato spaces and its application 总被引:2,自引:0,他引:2
Yang Dachun 《分析论及其应用》1994,10(4):85-99
Let 1<p<∞, α≥0 andK be a local field. In this paper, the author introduces the spaces J
p
α
(K) and the central Campanato spaces
as well as the Sp,α- and S
p,α
+
-type singular integrals. Then, the author investigates the behavior of these singular integrals and their altered operators
on these spaces.
The research was supported by the NNSF of China. 相似文献
9.
10.
Singular integrals and commutators on homogeneous groups 总被引:2,自引:0,他引:2
Let G be a homogeneous group. In this paper, the authors establish several general theorems for the boundedness of sublinear operators and commutators generated by linear operators and BMO(G)functions on the weighted Lebesgue space on G. The conditions of these theorems are satisfied by many important operators in analysis and these operators satisfy only some weak conditions on the size of operators and are known to be bounded in the unweighted case. Some of these theorems are best possible even when G is the Euclidean space. The authors also give some applications of their theorems to the boundedness on weighted spaces of rough singular integrals, oscillatory integrals, parabolic singular integrals, their commutators and the maximal operators associated with them. 相似文献