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Although simulation results for gaseous adsorption on a surface of infinite extent, modeled with periodic conditions at the boundaries of the simulation box, agree with experimental data at high temperatures, simulated isotherms at temperatures below the triple point temperature show unphysical substeps because of the compromise of interactions within the box and interactions between the box and its mirror image boxes. This has been alleviated with surfaces of finite dimensions (Loi, Q. K.; Colloids Surf., A2021, 622, 126690and Castaño Plaza, O.; Langmuir2023, 39(21), 7456–7468) to account for free boundaries at the adsorbate patch on the surface, and the critical parameter of this model substrate is the size of the finite surface. If it is too small, the adsorbate patch does not model the physical reality; however, if it is too large, the computation time is excessive, making the simulation impractical. In this study, we used carbon dioxide/graphite as the model system to explore the effects of finite dimensions on the description of experimental data of Terlain, A.; Larher, Y.Surf. Sci.1983, 125(1), 304–311, especially for temperatures below the bulk triple point temperature. With the appropriate choice of graphene size, we derived the 2D triple point and 2D critical point temperatures of the monolayer, and most importantly, for temperatures below the 2D critical point temperature, the adsorption mechanism for the formation of the monolayer is due to the interplay between the boundary growth process and the vacancy filling. The extent of this interplay is found to depend on the fractional coverage of the surface.

Plastic trash can be converted into activated carbon, which produces a product that is both useful and profitable, whilst also providing an environmentally friendly alternative. In this study, using a simple one-step chemical activation process with KOH, we successfully synthesized high-quality activated carbon from polyvinyl chloride (PVC), a common plastic. A thorough investigation was conducted into the effects of different processing parameters on the quality of the activated carbon made from PVC plastic, such as the PVC:KOH ratio, activation temperature and time. After determining the ideal parameters to optimize the iodine adsorption capacity, it was discovered that a PVC:KOH ratio of 1:2, an activation temperature of 500 °C and a 15-minute duration produced the best results. After 15minutes of adsorption and 1gL-1of adsorbent, the resultant activated carbon showed remarkable adsorption effectiveness for the organic dye methylene blue (MB), with a removal percentage of almost 97% at an MB concentration of 20 ppm. Furthermore, the impact of solution pH on the efficacy of MB adsorption was investigated and it was determined that the ideal pH range for the adsorption process was between 9 and 11. The MB adsorption isotherm was studied using the Langmuir and Freundlich models in order to have a deeper understanding of the adsorption behavior. Based on the calculated maximum MB adsorption capacity of around 97.1mgg-1, the results showed that the adsorption process adhered to the Langmuir adsorption isotherm model throughout. The adsorption kinetics and reusability of the activated carbon were also investigated. These results highlight the potential of activated carbon based on PVC as a successful adsorbent for the removal of organic dyes from aqueous solutions.

In this paper, we prove the boundedness of matrix Hausdorff operators and rough Hausdorff operators in the two weighted Herz-type Hardy spaces associated with both power weights and Muckenhoupt weights. By applying the fact that the standard infinite atomic decomposition norm on two weighted Herz-type Hardy spaces is equivalent to the finite atomic norm on some dense subspaces of them, we generalize some previous known results due to Chen et al. [7] and Ruan, Fan [35].

People who inject drugs (PWID) have a high incidence of HIV, little access to antiretroviral therapy (ART) and medication-assisted treatment (MAT), and high mortality. We aimed to assess the feasibility of a future controlled trial based on the incidence of HIV, enrolment, retention, and uptake of the intervention, and the efficacy of an integrated and flexible intervention on ART use, viral suppression, and MAT use.

Photocatalysts are an attractive solution for pollutant degradation under sunlight irradiation. One approach that has been proposed to enhance their activity is to combine two semiconductors, which can broaden the photon energy harvesting regions and improve charge separation. Herein, a facile approach to fabricating a g-C3N4@porphyrin nanorods hybrid material is presented using CTAB surfactant-assisted self-assembly of monomeric porphyrin molecules and g-C3N4 nanomaterials. Using different technical methods, the hybrid material was studied, and it was found that the porphyrin nanorods on the surface of g-C3N4were all in the same place. The photocatalytic performance of the hybrid material was evaluated by investigating its behavior for the photo-oxidation and -degradation of Cr6+ions and methylene blue organic dye under simulated sunlight irradiation. High photocatalytic performance towards these two pollutants was exhibited by the hybrid material with a removal percentage of nearly 100% after 100min of reaction time under the simulated sunlight spectrum. Also, a possible photocatalytic mechanism of the C3N4@porphyrin nanorods photocatalyst was proposed. This mechanism involved the efficient separation and transfer of photo-induced electrons and holes on the surface of the hybrid material. This work offers a simple and efficient method for creating high-performance photocatalysts, and we have made progress in our understanding of their photocatalytic mechanisms. The findings have important implications for wastewater treatment and solar energy conversion. The use of this hybrid material may contribute to addressing environmental challenges and assist in building sustainable energy systems.

Bronchoscopic lung volume reduction (BLVR) for the treatment of emphysema was originally developed in the early 2000’s as a minimally invasive alternative to lung volume reduction surgery (LVRS). Endobronchial valves (EBV) for BLVR are an advancing “guideline treatment” in the treatment of advanced emphysema. Placement of small, one-way valves into segmental or subsegmental airways can induce lobar atelectasis for portions of diseased lung. This results in the reduction of hyperinflation along with improvements in diaphragmatic curvature and excursion. This recommendation stemmed from two decades of validating evidence from randomized controlled trials investigating safety and efficacy, selection criteria, and procedural and post-procedure management. Appropriate patient selection is essential for procedural success using EBV. Many factors are included in determining if a patient is an acceptable candidate for BLVR. After the valve size has been chosen for a specific airway, valves are deployed into the airway for occlusion. As a result, patient functionality is significantly improved using BLVR by both objective and subjective measurements.

Observing marine mammal (MM) populations continuously in time and space over the immense ocean areas they inhabit is challenging but essential for gathering an unambiguous record of their distribution, as well as understanding their behaviour and interaction with prey species. Here we use passive ocean acoustic waveguide remote sensing (POAWRS) in an important North Atlantic feeding ground to instantaneously detect, localize and classify MM vocalizations from diverse species over an approximately 100,000 km2region. More than eight species of vocal MMs are found to spatially converge on fish spawning areas containing massive densely populated herring shoals at night-time and diffuse herring distributions during daytime. We find the vocal MMs divide the enormous fish prey field into species-specific foraging areas with varying degrees of spatial overlap, maintained for at least two weeks of the herring spawning period. The recorded vocalization rates are diel (24 h)-dependent for all MM species, with some significantly more vocal at night and others more vocal during the day. The four key baleen whale species of the region: fin, humpback, blue and minke have vocalization rate trends that are highly correlated to trends in fish shoaling density and to each other over the diel cycle. These results reveal the temporospatial dynamics of combined multi-species MM foraging activities in the vicinity of an extensive fish prey field that forms a massive ecological hotspot, and would be unattainable with conventional methodologies. Understanding MM behaviour and distributions is essential for management of marine ecosystems and for accessing anthropogenic impacts on these protected marine species.

Portland cement is one of most important construction and building materials and its properties depend strongly on the mineralogical composition. Consequently, accurate analysis of the mineralogical composition of anhydrous Portland cement is crucial for both product quality control and optimisation of performance following initial hydration. In the latter sense, analysis of the mineralogical composition of hydrated Portland cement paste is critical to understand (1) the mechanism and kinetics of hydration of unmodified pastes and those modified with additives and (2) the resultant properties of cement pastes, mortars, and concretes. Such analyses typically are undertaken by quantitative X-ray diffraction (XRD).The present work reviews current practices in quantitative XRD analysis of anhydrous and hydrated Portland cement. To this end, Part 1 of this two-part work briefly mentions the point-counting method and the Bogue calculation method. The more commonly applied internal standard method and reference intensity ratio (RIR) method are discussed in more detail.

The present work reviews current practices in quantitative XRD analysis of anhydrous and hydrated Portland cement. While Part 1 of this two-part work reviews the conventional internal standard method and the reference intensity ratio (RIR) method, Part 2 reviews the more commonly used computer-based methods, which include the Rietveld method (with or without internal standard) and the G-factor method (with external standard). Further, some critical general aspects of the experimental procedures that affect the accuracy of the analysis are discussed.

AbstractIn this paper, the compositional pattern of essential oils from five plants in the genus Litsea(Lauraceae family) cultivated in Vietnam, were being reported. The air-dried plant materials were hydrodistilled and the oils were analysed by Gas chromatography-flame ionization detector (GC-FID) and Gas chromatography coupled with Mass spectrometry (GC-MS). The leaf oil of Litsea helferiHook.f., was rich in limonene (17.5 %), β-caryophyllene (14.2 %), bicyclogermacrene (13.1 %), bicycloelemene (12.4 %) and α-phellandrene (8.0 %). The main constituents of Litsea ferrugineaLiou., leaf oil were dominated by monoterpenes comprising of sabinene (34.5 %), α-pinene (10.1 %), γ-terpinene (7.8 %), limonene (6.9 %) and terpinen-4-ol (6.6 %). The quantitative significant constituents of the leaf oil of Litsea verticillataHance were also monoterpene compounds represented by linalool (23.4 %), α-pinene (26.1%) and β-pinene (11.7 %). In addition, the monoterpene hydrocarbons (E)-β-ocimene (57.4 %), along with α-pinene (7.8 %) and β-pinene (7.3 %) were the main constituents in the leaf oil of Litsea glutinosa(Lour.) C. B. Rob. The main compounds in the leaf, stem, fruits and roots oils of Litsea cubeba(Lours.) Pers., were (Z)-citral (32.9-66.1 %), sabinene (1.4-14.2 %), limonene (7.0-13.6 %) and linalool (1.9-9.5 %). The chemical compositions of L. helferi, L. ferrugineaand L. verticillataare being reported for the first time.

Despite the potential of remote sensing for monitoring reservoir operation, few studies have investigated the extent to which reservoir releases can be inferred across different spatial and temporal scales. Through evaluating 21 reservoirs in the highly regulated Greater Mekong region, remote sensing imagery was found to be useful in estimating daily storage volumes for within‐year and over‐year reservoirs (correlation coefficients [CC] ≥ 0.9, normalized root mean squared error [NRMSE] ≤ 31%), but not for run‐of‐river reservoirs (CC < 0.4, 40% ≤ NRMSE ≤ 270%). Given a large gap in the number of reservoirs between global and local databases, the proposed framework can improve representation of existing reservoirs in the global reservoir database and thus human impacts in hydrological models. Adopting an Integrated Reservoir Operation Scheme within a multi‐basin model was found to overcome the limitations of remote sensing and improve streamflow prediction at ungauged cascade reservoir systems where previous modeling approaches were unsuccessful. As a result, daily regulated streamflow was predicted competently across all types of reservoirs (median values of CC = 0.65, NRMSE = 8%, and Kling‐Gupta efficiency [KGE] = 0.55) and downstream hydrological stations (median values of CC = 0.94, NRMSE = 8%, and KGE = 0.81). The findings are valuable for helping to understand the impacts of reservoirs and dams on streamflow and for developing more useful adaptation measures to extreme events in data sparse river basins. Satellite images are useful to estimate daily storage volumes for within‐year, over‐year reservoirs, but not for run‐of‐river reservoirsThe proposed framework can improve representation of local dams in the global reservoir databases and human impacts in hydrological modelsDaily regulated streamflow can be reasonably modeled by an integrated reservoir operation scheme of a multi‐basin model and satellite images Satellite images are useful to estimate daily storage volumes for within‐year, over‐year reservoirs, but not for run‐of‐river reservoirs The proposed framework can improve representation of local dams in the global reservoir databases and human impacts in hydrological models Daily regulated streamflow can be reasonably modeled by an integrated reservoir operation scheme of a multi‐basin model and satellite images

The occurrence of a chain reaction from blast on atmospheric storage tanks in oil and chemical facilities is hard to predict. The current French practice for SEVESO facilities ignores projectiles and assumes a critical peak overpressure value observed from accident data. This method could lead to conservative or dangerous assessments. This study presents various simple mechanical models to facilitate quick effective assessment of risk analysis, the results of which are compared with the current practice. The damage modes are based on experience of the most recent accidents in France. Uncertainty propagation methods are used in order to evaluate the sensitivity and the failure probability of global tank models for a selection of overpressure signatures. The current work makes use of these evaluations to demonstrate the importance of a dynamic analysis to study domino effects in accidents.L'occurrence de réaction en chaîne, dite réaction par effets dominos, sur les réservoirs de stockage atmosphérique suite à une explosion accidentelle dans les installations pétrochimiques est difficile à prévoir. La pratique actuelle française pour les installations SEVESO consiste à ignorer les projectiles et à assumer une valeur de surpression maximale admissible pour les effets de souffle. Cette méthode est susceptible de conduire à des évaluations conservatrices ou dangereuses. Cette étude présente divers modèles mécaniques simples pouvant permettre une évaluation efficace et rapide des risques d'effet dominos. Les modes de comportement des réservoirs sont basées sur l'expérience des plus récents accidents en France. Plusieurs méthodes de propagation des incertitudes sont utilisées afin d'évaluer les sensibilités et la probabilité de défaillance des modèles de réservoir pour une sélection de signaux de surpression. L'étude aboutie sur la sélection de paramètres et de modèles dynamiques pertinents pour l'étude des effets dominos.

The determination of the properties of porous solids remains an integral element to the understanding of adsorption, transport and reaction processes in new and novel materials. The advent of molecular simulation has led to an improved understanding and prediction of adsorption processes using molecular models. These molecular models have removed the constraints of traditional adsorption theories, which require rigid assumptions about the structure of a material. However, even if we possess a full molecular model of a solid, it is still desirable to define the properties of this solid in a standard manner with quantities such as the accessible volume, surface area and pore size distribution. This talk will present Monte Carlo integration methods for calculating these quantities in a physically meaningful and unambiguous way. The proposed methods for calculating the surface area and pore size distribution were tested on an array of idealised solid configurations including cylindrical and cubic pores. The method presented is adequate for all configurations tested giving confidence to its applicability to disordered solids. The method is further tested by using several different noble gas probe molecules. Finally, the results of this technique are compared against those obtained by applying the BET equation for a range of novel materials.

Abstract We present results of application of the density functional theory (DFT) to adsorption and desorption in finite and infinite cylindrical pores accounting for the density distribution in radial and axial directions. Capillary condensation via formation of bridges is considered using canonical and grand canonical versions of the 2D DFT. The potential barrier of nucleation is determined as a function of the bulk pressure and the pore diameter. In the framework of the conventional assumptions on intermolecular interactions both 1D and 2D DFT versions lead to the same results and confirm the classical scenario of condensation and evaporation: the condensation occurs at the vapor-like spinodal point, and the evaporation corresponds to the equilibrium transition pressure. The analysis of experimental data on argon and nitrogen adsorption on MCM-41 samples seems to not completely corroborate this scenario, with adsorption branch being better described by the equilibrium pressure – diameter dependence. This points to the necessity of the further development of basic representations on the hysteresis phenomena.

We present a new approach accounting for the non‐additivity of attractive parts of solid–fluid and fluid–fluid potentials to improve the quality of the description of nitrogen and argon adsorption isotherms on graphitized carbon black in the framework of non‐local density functional theory. We show that the strong solid–fluid interaction in the first monolayer decreases the fluid–fluid interaction, which prevents the two‐dimensional phase transition to occur. This results in smoother isotherm, which agrees much better with experimental data. In the region of multi‐layer coverage the conventional non‐local density functional theory and grand canonical Monte Carlo simulations are known to over‐predict the amount adsorbed against experimental isotherms. Accounting for the non‐additivity factor decreases the solid–fluid interaction with the increase of intermolecular interactions in the dense adsorbed fluid, preventing the over‐prediction of loading in the region of multi‐layer adsorption. Such an improvement of the non‐local density functional theory allows us to describe experimental nitrogen and argon isotherms on carbon black quite accurately with mean error of 2.5 to 5.8% instead of 17 to 26% in the conventional technique. With this approach, the local isotherms of model pores can be derived, and consequently a more reliable pore size distribution can be obtained. We illustrate this by applying our theory against nitrogen and argon isotherms on a number of activated carbons. The fitting between our model and the data is much better than the conventional NLDFT, suggesting the more reliable PSD obtained with our approach.

We used the setting of clinically indicated internal carotid artery balloon test occlusions in 44 patients with inoperable carotid cavernous aneurysms or head and neck tumours to examine real-time changes in higher cerebral function that correlate with specific levels of cerebral blood flow. By making detailed haemodynamic and neurobehavioural measurements during the 30 min the carotid artery was occluded, we were able to quantify higher cerebral function patterns in relation to absolute cerebral blood flow (CBF) levels. We found that once the carotid artery was occluded, patients whose CBF averaged 47 ml/100 g/min (no different from baseline) maintained consistent performance on a sustained attention task; those whose CBF dropped to an average 37 ml/100 g/min had a reversible deterioration of sustained attention, and those whose CBF fell to 27 ml/100 g/min had impaired sustained attention that persisted until the carotid occlusion was reversed. The relevance of these results to the pathological state of clinical stroke is discussed with respect to the haemodynamic and physiological mechanisms that may determine how brain function is lost and regained in the setting of acute cerebral hypoperfusion.

We used the setting of clinically indicated internal carotid artery balloon test occlusions in 44 patients with inoperable carotid cavernous aneurysms or head and neck tumours to examine real-time changes in higher cerebral function that correlate with specific levels of cerebral blood flow. By making detailed haemodynamic and neurobehavioural measurements during the 30 min the carotid artery was occluded, we were able to quantify higher cerebral function patterns in relation to absolute cerebral blood flow (CBF) levels. We found that once the carotid artery was occluded, patients whose CBF averaged 47 ml/100 g/min (no different from baseline) maintained consistent performance on a sustained attention task; those whose CBF dropped to an average 37 ml/100 g/min had a reversible deterioration of sustained attention, and those whose CBF fell to 27 ml/100 g/min had impaired sustained attention that persisted until the carotid occlusion was reversed. The relevance of these results to the pathological state of clinical stroke is discussed with respect to the haemodynamic and physiological mechanisms that may determine how brain function is lost and regained in the setting of acute cerebral hypoperfusion.

This study assessed the feasibility of augmenting cerebral blood flow (CBF) and decreasing hemispheric cerebrovascular resistance (CVR) by intracarotid papaverine during acute cerebral hypotension. Awake patients (n 10) undergoing transfemoral balloon occlusion of an internal carotid artery (ICA) with nitroprusside (SNP)-induced systemic hypotension (10 reduction of mean arterial pressure) were studied. We measured mean femoral artery pressure (MAP), mean distal ICA pressure (P ica), and CBF (intracarotid 133Xe) at two time points before and after intracarotid papaverine infusion (1 or 7 mg/min). Two patients became symptomatic immediately after ICA occlusion and were excluded. One patient developed a focal seizure during papaverine infusion. In another, the occlusion balloon deflated prematurely. Of the remaining six patients, two of the three patients who received high-dose papaverine (7 mg/min) developed transient obtundation. The remaining three patients, who received low-dose papaverine (1 mg/min), did not develop any neurologic symptoms. There was a trend for intracarotid papaverine to increase hemispheric CBF by 36 (33 ± 10 versus 45 ± 22 ml · 100 g−1· min−1, P.084, n 6); papaverine decreased CVR from 1.3 ± 0.4 to 1.0 ± 0.3 mm Hg · ml−1· 100 g−1· min−1(P.049). There was no significant change in heart rate, MAP, or P icaduring experimental protocol. Manipulation of CVR by intracarotid papaverine during acute hemispheric arterial hypotension appears to be feasible. Further studies are needed to establish safety and efficacy.

The clinical nurse researcher (CNR) is emerging as an integral part of every major medical center. The CNR has six basic roles: facilitate the conduct of research projects; stimulate staff to conduct research: upgrade the research skills of the staff; participate on committees related to research; conduct and disseminate research; and obtain funding for research studies. Readiness issues for military missions, health promotion, and disease management and prevention are consistently of interest. The CNR should be an active participant on the institutional review board and should conduct primary studies that further the reputation of the facility. The viability of any military research program today is contingent on procurement of funding; therefore, the CNR must refine skills in grantsmanship. The demands of the medical facility and the needs of the staff must be a prime consideration in the development of the role of the CNR.

The cyclic AMP response element (CRE) of the rat phosphoenolpyruvate carboxykinase (PEPCK) gene promoter is required for a complete glucocorticoid response. Proteins known to bind the PEPCK CRE include the CRE-binding protein (CREB) and members of the CCAAT/enhancer-binding protein (C/EBP) family. We took two different approaches to determine which of these proteins provides the accessory factor activity for the glucocorticoid response from the PEPCK CRE. The first strategy involved replacing the CRE of the PEPCK promoter/chloramphenicol acetyltransferase reporter plasmid (pPL32) with a consensus C/EBP-binding sequence. This construct, termed pDeltaCREC/EBP, binds C/EBPalpha and beta but not CREB, yet it confers a nearly complete glucocorticoid response when transiently transfected into H4IIE rat hepatoma cells. These results suggest that one of the C/EBP family members may be the accessory factor. The second strategy involved co-transfecting H4IIE cells with a pPL32 mutant, in which the CRE was replaced with a GAL4-binding sequence (pDeltaCREGAL4), and various GAL4 DNA-binding domain (DBD) fusion protein expression vectors. Although chimeric proteins consisting of the GAL4 DBD fused to either CREB or C/EBPalpha are able to confer an increase in basal transcription, they do not facilitate the glucocorticoid response. In contrast, a fusion protein consisting of the GAL4 DBD and amino acids 1-118 of C/EBPbeta provides a significant glucocorticoid response. Additional GAL4 fusion studies were done to map the minimal domain of C/EBPbeta needed for accessory factor activity to the glucocorticoid response. Chimeric proteins containing amino acid regions 1-84, 52-118, or 85-118 of C/EBPbeta fused to the GAL4 DBD do not mediate a glucocorticoid response. We conclude that the amino terminus of C/EBPbeta contains a multicomponent domain necessary to confer accessory factor activity to the glucocorticoid response from the CRE of the PEPCK gene promoter.

Summary:  Objective. Cardiopulmonary bypass with profound hypothermia and circulatory arrest has seen a resurgence as an adjunct technique in neurological surgery. We report our experience with this technique in treating seven complex vertebro-basilar aneurysms.  Methods. Skull base approaches were used in all cases, providing excellent exposure and minimizing brain retraction. There were six basilar artery aneurysms and one giant fusiform vertebro-basilar artery aneurysm. All aneurysms but one had an apparent neck, which could be clipped. The fusiform vertebro-basilar artery aneurysm was trapped, partially resected, and the circulation was re-established with a saphenous vein graft from the cervical internal carotid artery to the mid-basilar artery.  Results. Five patients had an excellent outcome and two had a good outcome at one year or at latest follow up. Two of the patients showed improvement of neurological deficits which were present before the surgical intervention.  Conclusion. Applying very strict selection criteria in this small series of patients with posterior circulation aneurysms, excellent or good results were achieved using the profound hypothermic circulatory arrest technique.

Shock waves impinging on axisymmetric converging passages of moderate wall angle undergo cyclical Mach reflection processes which are generally not self-similar during progression through the contraction. This paper presents the results of shock tube experiments in air where shocks of moderate strength are incident on cones having a range of wall angles of 10° to 30°. Mach reflection is maintained as the dominant reflection process throughout this range but the number of cycles decreases as wall angle increases. A ray-shock approach, used to calculate the triple-point trajectories gives good agreement with the experimental locations of their intersections with the centreline and wall.

A Semimechanistic mathematical model is developed which describes the growth of Rhizopus oligosporusin a model solid‐state fermentation system. Equations are presented for the release of glucoamylase, the diffusion of glucoamylase, the hydrolysis of starch, the generation and diffusion of glucose, and the uptake of glucose and conversion into new biomass. Good agreement of the model with the experimental data was obtained only after the glucoamylase diffusivity and the maximum specific glucose uptake rate were altered from their originally determined values. The model recognizes the distributed nature of the solid‐state fermentation and therefore is able to predict the concentration profiles of the system components within the substrate. The model provides an insight into the possible rate‐limiting steps in solid‐state fermentation—the generation of glucose within the substrate and the resulting availability of glucose at the surface.

By using a previously proposed novel integral transform approach, approximate analytical solutions for a certain class of concentration-dependent diffusion and reaction problems can be obtained. Three example problems of increasing complexity are presented to demonstrate the versatility of this technique. Perturbation techniques are also employed to determine asymptotic behaviour of the solutions in the limit of large or small values of some parameters.

An approximation formula for finite Sturm-Liouville integral transforms of nonlinear functions allows determination of approximate analytical solutions to a certain class of nonlinear boundary value problems. The proposed method is extremely powerful in analysis of a variety of chemical engineering models. The influence of the degree of nonlinearity of the nonlinear term on results obtained using the approximate transform formula is investigated numerically. An iterative procedure in transform space is described for improving solution accuracy, and fast convergence is observed in three illustrative examples. The technique yields solutions which can be related to bounds on the exact solution derived by Kalaba. The asymptotic solution for the mode error, which is the error in approximating the nonlinear function in transform space, is obtained analytically.

The effect of micropore diffusion, macropore diffusion and adsorption on the transient uptake of porous solids having bimodal pore size distribution (for example, zeolites) is theoretically investigated in this paper. Two models commonly used in the literature - the pore diffusion model and the surface diffusion model - are considered and their equivalence is discussed. The bimodal diffusion model equations are solved analytically by using a generalized integral transform method. The solutions for the micropore, macropore concentrations and the fractional uptake are presented. Since two different processes control the transient uptake, the asymptotic solutions for micropore diffusion control case and macropore diffusion control case are obtained by using perturbation methods, so that these asymptotic solutions can be compared with that when these two processes equally contribute to the transient uptake.

In this paper, we provide exact analytical solutions for a new method of constant molar flow of pure gas into a reservoir containing solid adsorbents having a bidispersed structure, such as zeolite, activated carbon and alumina. Depending on the diffusion mechanism, two models are proposed under the isothermal conditions and linear isotherm. One is applicable to zeolite, and the other for alumina and activated carbon. The solutions of these two models are in the form of an infinite series, and its eigenvalues are determined from a transcendental equation. This transcendental equation is such that the eigenvalues are lumped into infinite but countable groups, and in each group there are infinite but countable eigenvalues. The dominant eigenvalues are generally the first ten to thirty eigenvalues (depending on the value of time at which the series is evaluated) in each group. The pressure response of the reservoir is a function of time as the result of the introduction of adsorbate into the reservoir, and as time is sufficiently large it asymptotes to a straight line, of which the slope is a function of the equilibrium parameters only and the intercept is found to be an explicit function of the equilibrium parameters as well as the diffusivities in the macropore and micropore.

In this paper we present a theoretical analysis of multicomponent adsorption dynamics of hydrocarbons into a medium-sized activated carbon. The mathematical model allows for the diffusions of the free and adsorbed species into the particle, with the driving force for the adsorbed species being the chemical potential gradient rather than the concentration gradient. The adsorbed species diffuse in two directions inside the particle. One direction is the direction along the particle coordinate while the other is the direction along the grain coordinate. The multicomponent adsorption equilibrium is calculated using the ideal adsorbed solution theory, with the single-component isotherm described by Langmuir equation.

Two models, the Help with the Assessment of Adenopathy in Lung cancer (HAL) and Help with Oncologic Mediastinal Evaluation for Radiation (HOMER), were recently developed to estimate the probability of nodal disease in patients with non-small cell lung cancer (NSCLC) as determined by endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA). The objective of this study was to prospectively externally validate both models at multiple centers.

A 49-year-old woman presenting with recurrent, reversible brainstem symptoms and a distal basilar artery aneurysm underwent balloon test occlusion. Five minutes after balloon inflation she developed a reversible isolated dysarthria. Despite failing the test occlusion (and after an additional brainstem event), the patient underwent surgery with placement of a clip across the basilar artery. The operation was tolerated without complication. The authors conclude that 1) pure dysarthria may be a symptom of temporarybasilar artery occlusion and 2) balloon testing may overestimate the risk of basilar artery clipping.