We have examined the effects of collisions among molecules desorbing from solid surfaces by means Monte Carlo simulations, and identified conditions under which to what extent these would influence experimentally observed product distributions. By simulating experiment performed Cowin et al. [Surf. Sci. 78, 545 (1978)] on laser induced desorption D2 tungsten, we found that at high coverages each desorbate makes average 2.9 decreases no very low coverages. These affect distribution such an...

Oligostilbenoids are polyphenols that widely distributed in nature with multifaceted biological activities. To achieve biomimetic synthesis of unnatural derivatives, we subjected three resveratrol analogues to oligomerization by means one-electron oxidants. Upon varying the metal oxidant (AgOAc, CuBr(2), FeCl(3)6 H(2)O, H(2)O/NaI, PbO(2), VOF(3)), solvent (over whole range polarities), and oxygenated substitution pattern starting material, stilbenoid oligomers totally different carbon...

The effects of gas-phase collisions in mixtures gases rapidly desorbed from surfaces are studied using direct Monte Carlo techniques. results compared with the observed desorption pure under similar conditions. translational energy distribution particles found to deviate Boltzmann and be well represented by ellipsoidal distributions. In this respect rapid process is have similarities expansion nozzle sources. influence mass, internal degrees freedom, surface coverage adsorbates on focusing,...

The influence of postdesorption collisions on the experimentally measured angular and energy distributions rapidly desorbed molecules is investigated using direct Monte Carlo simulation procedures. By simulating desorption NO from LiF(100), we find that have a significant effect final angular, rotational energy, translational molecules.

Microencapsulation is a promising approach in drug delivery to protect the from degradation and allow controlled release of body. Fucoxanthin-loaded microsphere (F-LM) was fabricated by two step w/o/w double emulsion solvent evaporation method with poly (L-lactic-coglycolic acid) (PLGA) as carrier. The effect four types surfactants (PVA, Tween-20, Span-20 SDS), homogenization speed, concentration PLGA polymer surfactant (PVA), respectively, on particle size morphology F-LM were investigated....

A variational transition-state theory study of the recombination/desorption rate H2 from a Si(111) surface using previously described Monte Carlo procedure [J. Chem. Phys. 83, 1389 (1985)] is reported. The potential-energy expressed as sum lattice potential, lattice-adatom interaction term, and an adatom–adatom interaction. Keating’s formulation with parameters suggested by Weber used for potential. adatom–lattice term written pairwise 60 Morse potentials each multiplied hyperbolic switching...

The dissociation dynamics of the RgI2 (Rg=Ar,Kr,Xe) van der Waals complexes have been studied using three-dimensional quasiclassical trajectories. Specifically, unimolecular RgI2(B 3π) with initial I2 vibrational excitation above Rg+I+I limit B 3π state was studied. In addition to complete atoms, iodine ‘‘recombination’’ observed be a major reaction channel. This result is interpreted as cage-like effect due inert gas atom, which also carries away large fraction energy when complex...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of reagent rotation on the cross section for reaction lithium + hydrogen fluoride .fwdarw. hydrogenI. NoorBatcha and N. SathyamurthyCite this: J. Am. Chem. Soc. 1982, 104, 6, 1766–1767Publication Date (Print):March 1, 1982Publication History Published online1 May 2002Published inissue 1 March 1982https://pubs.acs.org/doi/10.1021/ja00370a066https://doi.org/10.1021/ja00370a066research-articleACS PublicationsRequest reuse permissionsArticle...

Fish gelatin nanoparticle is produced using Tilapia fish skin for the first time by two-step desolvation method. chosen producing nanoparticles because no experiment have been done in and to counter problem associated with use of mammalian gelatin, such as bovine spongiform encephalopathy disease. The effects several factors on particle size pH, acetone concentration, glutaraldehyde volume, stirring speed are evaluated. Optimum conditions formation obtained response surface optimum can be pH...

The mammalian hyaluronidase degrades hyaluronic acid by the cleavage of β-1,4-glycosidic bond furnishing a tetrasaccharide molecule as main product which is highly angiogenic and potent inducer inflammatory cytokines. Ursolic 1, isolated from Prismatomeris tetrandra, was identified having potential to develop inhibitors hyaluronidase. A series ursolic analogues were either synthesized via structure modification 1 or commercially obtained. evaluation inhibitory activity these compounds on...

Adsorption and surface diffusion of silicon on the Si(100) plane have been investigated by classical trajectory methods using a realistic potential-energy surface. The calculated sticking probability for adsorption is 0.965 at 1500 K independent temperature. coefficient Si evaluated modeling process as jumping adatom from one site to another. this approach given D=(6.35±1.44)×10−4 exp(−3.63±0.47 kcal mol−1/RT) cm2 s−1. This value found be in good agreement with coefficients long-time...

Cancer is one of the deadliest diseases in world and responsible for around 13% all deaths worldwide.Cancer incidence rate growing at an alarming world.Despite fact that cancer preventable curable early stages, vast majority patients are diagnosed with very late.Furthermore, commonly comes back after years treatment.Therefore, it paramount importance to predict recurrence so specific treatments can be sought.Nonetheless, conventional methods predicting rely solely on histopathology results...

The dissociative chemisorption and scattering of H2 on an unreconstructed Si(111) surface has been investigated using classical trajectories a potential-energy previously used to study recombination/desorption from [J. Chem. Phys. 85, 3081 (1986)]. results show be elastic predominately specular. scattered translational energy distributions are broadened but there is virtually no change in the average values. There very little transfer or internal modes. Lower limits sticking probabilities...

Vibrational threshold equal to the barrier height for an endothermic reaction: Li+FH→LiF+H on ab initio potential energy surface is considered. (AIP)

After numerous breakthroughs in medicine, microbiology, and pathology the past century, lung cancer still remains as a leading cause of cancer-related death even developed countries.Lung accounts roughly for 30% all deaths world.Diagnosis treatments are based on traditional histopathology.It is paramount importance to predict survivability patients early stages so that specific can be sought.Nonetheless, histopathology has been shown by previous studies inadequate predicting development...

A general method to calculate a lower bound and an estimated upper for the surface diffusion coefficient from jump frequencies of adatom one absorption site another has been formulated. This applied Si on Si(111). Keating’s potential used Si(111) lattice. The interaction between lattice is pairwise sum 60 Morse potentials involving atoms in first second layers crystal. formulation predicts existence two different types adsorption sites surface. these have calculated by classical trajectory...

We have simulated the photodissociation of CH3Br adsorbed at a variety surfaces. considered smooth LiF (001) substrate and three rough surfaces which were constructed by removing atoms from surface. also several same structure as β phase solid to simulate dissociation high coverages adsorbate where ice is formed. The simulations performed using stochastic classical trajectory method. asymptotic photofragment kinetic energy angular distributions determined compared with experimental results...

The recombination/desorption of H2 and the desorption hydrogen atoms from a Si(111) surface have been investigated using Monte Carlo transition-state theory methods with biased random walk. Rate coefficients, activation energies, preexponential factors, angular distributions computed for both reaction channels. distribution polarization angles rotational momentum vector is also reported. potential-energy expressed as sum lattice potential, lattice–adatom interaction term, an adatom–adatom...

The semiempirical valence-bond surface formulated by Viswanathan et al. [J. Phys. Chem. 89, 1428 (1985)] for the unimolecular dissociation of SiH2 has been fitted to an analytical function type suggested Murrell and co-workers 88, 4887 (1984)]. accurately represents most experimental CI results. dynamics form Si H2 have investigated classical trajectory methods on this surface. effect describing initial state molecule using normal local mode approximations studied. In spite presence heavier...