Publications

Several types of mesoporous aluminosilicates were synthesized and evaluated in the catalytic isomerization of n-hexane, both with and without Pt nanoparticles loaded into the mesopores. The materials investigated included mesoporous MFI and BEA type zeolites, MCF-17 mesoporous silica, and an aluminum modified MCF-17. The acidity of the materials was investigated through pyridine adsorption and Fourier Transform-Infrared Spectroscopy (FT-IR). It was found that the strong Brönsted acid sites in the micropores of the zeolite catalysts facilitated the cracking of hexane. However, the medium strength acid sites on the Al modified MCF-17 mesoporous silica greatly enhanced the isomerization reaction. Through the loading of different amounts of Pt into the mesopores of the Al modified MCF-17, the relationship between the metal nanoparticles and acidic sites on the support was revealed.

Condensation reactions such as Guerbet and aldol are important since they allow for C-C bond formation and give higher molecular weight oxygenates. An initial study identified Pd-supported on hydrotalcite as an active catalyst for the, transformation, although this catalyst showed extensive undesirable decarbonylation. A catalyst containing Pd and Cu in a 3:1 ratio dramatically decreased decarbonylation, while preserving the high catalytic rates seen with Pd-based catalysts. A combination of XRD, EXAFS, TEM, and CO chemisorption and TPD revealed the formation of CuPd bimetallic nanoparticles with a Cu-enriched surface. Finally, density functional theory studies suggest that the surface segregation of Cu atoms in the bimetallic alloy catalyst produces Cu sites with increased reactivity, while the Pd sites responsible for unselective decarbonylation pathways are selectively poisoned by CO.

Despite the presence of reduced drug susceptibility, antiretroviral-drug therapy can provide immunologic and virologic benefit. This benefit reflects continued antiviral-drug activity and the maintenance of a viral population with a reduced replicative capacity.

In this work, we visualize and quantify the microstructure evolution in the composite electrode after solid-state battery (SSB) cycling. The observed severe mechanical degradation highlights the importance of mechanical considerations in SSB design.

The concentrations of photosystem I (PSI) and photosystem II (PSII) reaction centers and the level of chloroplast reaction center gene transcripts were determined in pea plants grown under different light-quality regimes. In plants grown in light primarily absorbed by PSI (“red” light), the PSII/PSI reaction center ratio was 2-fold greater than that in plants grown in PSII-sensitizing (“yellow”) light. In addition, the ratio of a PSII gene ( psbB ) transcript to a PSI gene ( psaA ) transcript was 2.6 times greater in red-grown plants relative to yellow-grown plants. Thus, a differential reaction-center concentration in the thylakoid membrane was accompanied by a differential expression of reaction center genes, suggesting that the synthesis of chloroplast membrane complexes and the assembly of photosystems are regulated by light quality at the transcriptional and/or post-transcriptional level.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The ambient‐temperature subcritical growth behavior of both long and microstructurally small cracks is investigated during cyclic‐fatigue loading in a SiC‐whisker‐reinforced alumina (Al 2 O 3 –SiC w ) ceramic composite (fracture toughness, K c ∼ 4.5 MPa · m 1/2 ). Based on long‐crack experiments using compact C(T) specimens, cyclic fatigue‐crack growth rates (over the range 10 −11 to 10 −5 m/cycle) are found to be sensitive to the applied stress‐intensity range and load ratio, and to show evidence of fatigue crack closure. Similar to other ceramic materials, under tension–tension loading the “long”(>3 mm) crack fatigue threshold, Δ K TH , was found to be on the order of 60% of K c . Conversely, “small”(1 to 300 μm) cracks grown from micro‐indents on the surface of cantilever‐beam specimens were observed to grow at applied Δ K levels some 2 to 3 times smaller than Δ K TH . similar to behavior widely reported for metallic materials. The observed small‐crack behavior is rationalized in terms of the residual stress field associated with the indent, and the restricted role of crack‐tip shielding (from mechanisms such as crack bridging, closure and deflection) with cracks of limited wake, analogous to closure effects with small fatigue cracks in metals. Consistent with the lack of zone‐shielding mechanisms in Al 2 O 3 –SiC w , under variable‐amplitude cyclic loading crack‐growth rates do not exhibit the marked transient response following block overload sequences as do transformation‐toughened ceramics or ductile metallic materials. Possible mechanisms for cyclic crack advance in reinforced ceramic‐matrix composite materials are discussed.

Here, we report NucRFAP-2, a nuclear-targeted, activity-based sensing ratiometric probe for formaldehyde (FA) detection, and apply it to identify new, human disease-relevant epigenetic contributors to the nuclear FA pool.

Interfacial deposition stability between Li metal and a solid electrolyte (SE) is important in preventing interfacial contact loss, mechanical fracture, and dendrite growth in Li-metal solid-state batteries (SSB). In this work, we investigate the deposition and mechanical stability at the Li metal/SE interface and its consequences (such as SE fracture and contact loss). A wide range of contributing factors are investigated, such as charge and mass transfer kinetics, the plasticity of Li metal and fracture of the SE, and the applied stack pressure. We quantify the effect of the ionic conductivity of the SE, the exchange current density of the interfacial charge-transfer reaction and SE surface roughness on the Li deposition stability at the Li metal/SE interface. We also propose a mechanical stability window for the applied stack pressure that can prevent both contact loss and SE fracture, which can be extended to other metal-electrode (such as Sodium) SSB systems.

Abstract We employed a unique murine intensive care unit (ICU) model allowing long‐term studies of the ICU condition (immobilization, paralysis, sedation and mechanical ventilation). This model resulted in a substantial loss of myofibrillar protein and muscle size. We hypothesized that an inhibitor of Janus kinase (JAK) activation of transcription 3 (STAT3 (signal transducer and activator of transcription 3)) phosphorylation would help to preserve muscle mass by stimulating the rate of protein synthesis. Sprague–Dawley rats were divided into a control group (CON, n = 5) and two groups exposed to the ICU condition for 8 days. One group was treated with a JAK/STAT3 inhibitor (JST, n = 5) and one without a JST (immobilized group, n = 3) inhibitor. To measure the fractional synthesis rate (FSR) of proteins across the muscle proteome, 2 H 2 O was administered as an intraparitoneal (IP) bolus followed by continuous infusion of 8% 2 H 2 O to maintain body water enrichment. Soleus, extensor digitorum longus (EDL), tibialis anterior (TA), gastrocnemius and diaphragm were obtained from all animals. Liquid chromatography–mass spectrometry (LC/MS–MS) analysis was used to measure protein FSR. Compared to CON myofibrillar protein FSR was decreased 39%–73%, with the decrease in gastrocnemius > soleus > TA > diaphragm > EDL. Sarcoplasmic protein FSR was decreased 38%–69%, with the decrease in gastrocnemius > TA > EDL > soleus > diaphragm. Mitochondrial protein FSR was decreased 34%–52%, with the decrease in TA > soleus > gastrocnemius > EDL > diaphragm. The decreases in protein flux rates by ontology corresponded broadly with function and fibre types. Immobilization resulted in profound and tissue‐specific decreases in protein FSR, with JAK/STAT3 showing a significant effect to preserve FSR, muscle mass and body weight. image Key points Mechanical silencing of skeletal muscle resulted in a large lowering of protein fractional synthesis rate (FSR) in all muscles measured, the extent of which was muscle‐ and fibre specific. All muscle protein ontologies were affected. A Janus kinase (JAK)/STAT inhibitor had a positive effect on body mass, muscle size and protein FSR.

Efficient and robust uncertainty quantification (UQ) is essential in aerospace systems, as emphasized by both NASA’s CFD Vision 2030 and Certification by Analysis (CbA) 2040 initiatives. However, the extensive computational resources required by traditional UQ methods, especially when coupled with high-fidelity computational fluid dynamics (CFD) simulations, pose significant barriers. Quantum computing (QC) has been identified by the CFD Vision 2030 study as a promising technology to address these challenges, but has not yet been extensively explored in the context of UQ. In this study, a Quantum Computing-based Monte Carlo (QCMC) algorithm is implemented using a Qiskit simulator. This method utilizes Quantum Amplitude Estimation (QAE), specifically tailored for near-term Noisy Intermediate-Scale Quantum (NISQ) computers. The QCMC method demonstrates comparable accuracy to classical Monte Carlo (MC) methods on a two-dimensional heat diffusion problem while reducing the required number of samples (oracle calls) by ∼8X. By substantially lowering the computational overhead of UQ, this quantum computing-based algorithm could be a promising tool required to enable robust uncertainty-informed aerospace design.