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11.
Raman scattering and relaxed fluorescence is observed upon cw laser excitation resonant with the lower vibrational manifold of the X(1Σo+u) → B(3Πo+u) transition of matrix isolated Br2 at liquid He temperatures. The excitation profile of the relaxed fluorescence maps out the resonances, but neither detectable enhancement of Raman scattering nor resonance fluorescence is observed.  相似文献   
12.
Applied Biochemistry and Biotechnology - Although lignocellulosic biomass and wastes are targeted as an attractive alternative fermentation feedstock for the production of fuel ethanol, cellulosic...  相似文献   
13.
A primary cleavage of aliphatic ozonides by electron-impact, implying O? O and C? C bond breaking, is described. This mode of degradation, which is not observed for aromatic ozonides, is fav oured by electron releasing substituents. For the cis and trans 4-methyl-2pentene ozonides, the ionization potentials are 8.81 and 8.86 (±0.5) eV, respectively. Two formation thresholds are observed for the [RCHO2]+ion which are interpreted in terms of different modes of ozonide cleavage.  相似文献   
14.
Radioligand therapy (RLT) is an emergent drug class for cancer treatment. The dose administered to cancer patients is constrained by the radiation exposure to normal tissues to maintain an appropriate therapeutic index. When a radiopharmaceutical or its radiometabolite is retained in the kidneys, radiation dose deposition in the kidneys can become a dose-limiting factor. A good exemplar is [177Lu]Lu-DOTATATE, where patients receive a co-infusion of basic amino acids for nephroprotection. Besides peptides, there are other classes of targeting vectors like antibody fragments, antibody mimetics, peptidomimetics, and small molecules that clear through the renal pathway. In this review, we will review established and emerging strategies that can be used to mitigate radiation-induced nephrotoxicity, with a focus on the development and incorporation of cleavable linkers for radiopharmaceutical designs. Finally, we offer our perspectives on cleavable linkers for RLT, highlighting future areas of research that will help advance the technology.  相似文献   
15.
A new family of non-symmetrical disubstituted dibenzophospholes possessing different steric and electronic effects have been synthesized and characterized. Their preliminary evaluation in rhodium-catalyzed hydroformylation reactions is presented.  相似文献   
16.
In this paper, it is shown how a percolation process can be used to describe the inhomogeneities of polymer concentration, appearing in gels prepared by random crosslinking of a semi-dilute solution, and how they are modified by swelling or stretching of the network. Neutron scattering experimental data are compared to the predictions of this model in the isotropic and anisotropic cases. A good agreement is found. In particular, “abnormal” butterfly patterns in the iso-intensity curves have been detected, as expected from the model.  相似文献   
17.
In plasma edge transport codes for nuclear fusion devices, fluid-neutral models offer an interesting alternative to the currently used kinetic Monte Carlo simulations, especially for cases of high ion-neutral collisionality. In this paper, we elaborate a separate neutral energy equation in the state-of-the-art SOLPS-ITER code suite, which previously assumed perfect ion-neutral temperature equilibration. Furthermore, we study the coupled plasma-neutral solutions for a range of divertor operating regimes, proving the validity of these fluid-neutral models for high-recycling and detached regimes.  相似文献   
18.
We demonstrate that betatron x-ray radiation accurately provides direct imaging of electrons trajectories accelerated in laser wakefields. Experimental far field x-ray beam profiles reveal that electrons can follow similar transverse trajectories with typical excursions of 1.5 microm+/-0.5 microm in the plane of laser polarization and 0.7 microm+/-0.2 microm in the plane perpendicular.  相似文献   
19.
The following results are obtained. (i) Let p, d, and k be fixed positive integers, and let G be a graph whose vertex set can be partitioned into parts V1, V2,…, Va such that for each i at most d vertices in V1Vi have neighbors in Vi+1 and r(Kk, Vi) p | V(G) |, where Vi denotes the subgraph of G induced by Vi. Then there exists a number c depending only on p, d, and k such that r(Kk, G)c | V(G) |. (ii) Let d be a positive integer and let G be a graph in which there is an independent set I V(G) such that each component of GI has at most d vertices and at most two neighbors in I. Then r(G,G)c | V(G) |, where c is a number depending only on d. As a special case, r(G, G) 6 | V(G) | for a graph G in which all vertices of degree at least three are independent. The constant 6 cannot be replaced by one less than 4.  相似文献   
20.
Belloncle VV  Rousseau M 《Ultrasonics》2006,45(1-4):188-195
The aim of this paper is to evaluate the influence of the surface free energy upon the propagation of the eigenmodes of structures, by studying successively (a) the Rayleigh wave for an elastic half-space, (b) the Lamb waves for an elastic layer, and (c) the guided modes for a tri-layer structure (e.g., metal/adhesive/metal). The surface free energy is a parameter which appears in the jump conditions of stresses and displacements at each interface, and which consequently modifies the eigenmodes, solutions of the boundary conditions system. As expected, the Rayleigh wave is dispersive and its velocity increases when the surface free energy increases. In the same way, the velocity of Lamb waves also increases except at normal angle of propagation where the surface free energy does not arise. Moreover, near the Rayleigh angle, the behaviour of the A0 and S0 Lamb modes varies strongly according to the surface free energy. Similar results are observed for the tri-layer structure.  相似文献   
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