Separations

The recently introduced solid-state modulator (SSM) is a compact and relatively simple all-in-one solution to thermal modulation for use in comprehensive two-dimensional gas chromatography (GC×GC). In this work, we assess the performance of this modulator through a detailed assessment of its temperature stability and temperature programming capabilities, and corresponding retention time reproducibility. Through replicate analysis, ²D retention time standard deviation was determined to be 0.014 s (ranging from 0.000–0.023 s), corresponding to less than a single acquisition datapoint. Additionally, ¹D retention time repeatability in GC×GC was assessed using a ‘super-resolution method’ designed to predict ¹D retention based on the modulated peak distribution, and was determined to be comparable to that of conventional GC-MS analysis. A benchmarking framework was developed, which can be applied to future performance evaluations of thermal and other modulators, allowing for a more systematic comparison of modulation strategies.

Blood is a key biological specimen in forensic analysis for both living and deceased individuals, playing a crucial role in drug testing, blood typing, DNA analysis, and bloodstain pattern examination. In forensics, the decomposition of blood holds particular importance because it is a major biological fluid in the human body and undergoes early chemical changes that attract insects and microorganisms to cadaveric sources. The odor signatures produced during the putrefactive process have recently gained forensic relevance, prompting studies to investigate volatile organic compounds (VOCs) from blood, tissues, animal proxies, and human cadavers to enhance human remains detection and recovery via technological or biological means. This study focuses on cadaveric blood odor profiling, evaluating VOC signatures from human cadavers in an anatomy laboratory using solid-phase micro-extraction (SPME) and gas chromatography–mass spectrometry (GC/MS) upon body receipt. A second phase entailed a degradation analysis using 7 human cadavers and a total of 28 postmortem samples repeatedly sampled over a 4-week period. The findings revealed an increasingly complex odor profile as decomposition progresses, with a notable rise in both the variety and concentration of VOCs. Room temperature samples exhibited a more diverse and rapid VOC release, while refrigerated samples showed slower degradation. These insights contribute to a deeper understanding of decomposition patterns and ultimately refine human remains detection methodologies.

The highly efficient performance of photoelectrochemical (PEC) water splitting is largely governed by the construction of active interfaces, especially for the star semiconductor/electrocatalyst system. However, traditional strategies struggle to optimize this critical process. To overcome this challenge, we report a fluorine (F) engineering strategy that enables the synchronous modulation of charge transfer and surface catalytic reaction dynamics in a BiVO₄/FeCoOOH-integrated photoanode. Various characterization methods confirm that F engineering can activate the BiVO₄/FeCoOOH/electrolyte interfaces. Benefiting from these positive effects, the optimized BiVO₄/FeCoOOH-F photoanode achieves a relatively high photocurrent density of 5.46 mA/cm² at 1.23 V vs. RHE, along with outstanding photostability and a small Tafel slope of 96.5 mV dec⁻¹. This study provides new insights into F-based interface manipulation, offering a promising route to developing high-performance semiconductor/electrocatalyst systems for efficient and stable PEC water splitting applications.