Full Energy Research Articles

Isomeric differentiation of bile acids using three‐dimensional MS2 spectrum

AbstractBile acids (BAs) currently occupy the research hotspot because of their unreplaceable physiological functions as well as their unique abilities to reflect the physiopathological status. It is always challenging to characterize BAs‐submetabolome using LC–MS/MS, primarily attributing to the high‐level structural diversity. The key obstructing confirmative identification is isomeric identification because of the inherent “isomer‐blind” disadvantage of MS/MS. The isomerism styles of BAs are broadly divided into: type‐I, 5α‐H and 5β‐H epimers; type‐II, α‐OH and β‐OH epimers; type‐III, C‐OH positional isomers; and type‐IV, hybrid isomers bearing two or more isomerism fashions. Herein, we aim to comprehensively pursue isomer‐selective clues for BAs through constructing three‐dimensional MS2 (3D‐MS2) spectrum that was accomplished by fortifying energy‐resolved MS (ER‐MS) program as the new dimension. The breakdown graphs of primary MS2 spectral signals composed of 3D‐MS2 spectrum namely full collision energy ramp (FCER)‐MS2 spectrum for each BA species after appropriate normalization, and seven isomeric BAs covering all isomerism styles were utilized as representative cases. After recording MS2 spectra with progressive CE levels, differences were observed for their FCER‐MS2 spectra. Diagnostic fragment ions (DFIs) occurred within type‐I, type‐II, type‐III or type‐IV isomers, and noteworthily, 2.02 Da neutral loss discriminated BAs containing cis‐6,7‐diol and trans‐6,7‐diol functional groups. Notably, the features such as the maximal relative ion intensity (RIImax) and optimal CE (OCE) enabled isomeric differentiation for all types, even type‐II and type‐III isomers. Above all, it is feasible to acquire in‐depth isomer‐selective MS/MS clues for BAs using FCER‐MS2 spectrum, regardless of the isomerism manner.

Exchange-only virial relation from the adiabatic connection.

The exchange-only virial relation due to Levy and Perdew is revisited. Invoking the adiabatic connection, we introduce the exchange energy in terms of the right-derivative of the universal density functional w.r.t. the coupling strength λ at λ = 0. This agrees with the Levy-Perdew definition of the exchange energy as a high-density limit of the full exchange-correlation energy. By relying on v-representability for a fixed density at varying coupling strength, we prove an exchange-only virial relation without an explicit local-exchange potential. Instead, the relation is in terms of a limit (λ ↘ 0) involving the exchange-correlation potential vxcλ, which exists by assumption of v-representability. On the other hand, a local-exchange potential vx is not warranted to exist as such a limit.

High-Pressure Phases of Boron Pnictides BX (X = As, Sb, Bi) with Quartz Topology from First Principles

The superdense hexagonal boron pnictides BX (X = As, Sb, Bi), whose structures are formed by distorted tetrahedra and characterized by a quartz-derived (qtz) topology, have been predicted from first principles as potential high-pressure phases. From full geometry structure relaxation and ground state energy calculations based on quantum density functional theory (DFT), qtz BX was found to be mechanically (elastic constants) and dynamically (phonons) stable. From the energy–volume equations of state, at high but experimentally accessible pressures, qtz boron pnictides were found to be more energetically favorable than corresponding cubic zinc–blende phases with diamond-like (dia) topology. According to the electronic band structures, the zinc–blende BX have larger band gaps than the qtz phases, which can be attributed to the higher covalence of the latter. A metallic behavior is only observed for qtz BBi, which is related to the dynamic instability as it follows from the phonon band structure.

Inter-subunit energy transfer processes in a minimal plant photosystem II supercomplex.

Photosystem II (PSII) is an integral part of the photosynthesis machinery, in which several light-harvesting complexes rely on inter-complex excitonic energy transfer (EET) processes to channel energy to the reaction center. In this paper, we report on a direct observation of the inter-complex EET in a minimal PSII supercomplex from plants, containing the trimeric light-harvesting complex II (LHCII), the monomeric light-harvesting complex CP26, and the monomeric PSII core complex. Using two-dimensional (2D) electronic spectroscopy, we measure an inter-complex EET timescale of 50 picoseconds for excitations from the LHCII-CP26 peripheral antenna to the PSII core. The 2D electronic spectra also reveal that the transfer timescale is nearly constant over the pump spectrum of 600 to 700 nanometers. Structure-based calculations reveal the contribution of each antenna complex to the measured inter-complex EET time. These results provide a step in elucidating the full inter-complex energy transfer network of the PSII machinery.

Experimental study on the seismic performance of concrete-filled steel tube columns with a multiple-chamber round-ended cross-section

Reinforced concrete bridge piers with round-ended sections are susceptible to bending, bending–shear, and shear failure after earthquakes in high-intensity areas, thus necessitating improved seismic performance. This study introduced a novel design for a concrete-filled steel tube (CFST) column, featuring a multi-chambered, round-ended cross-section. The use of longitudinal and transverse stiffeners divided the column section into distinct chambers, thereby enhancing the seismic performance of the columns. A total of 12 groups of static tests were performed to examine the effect of chamber layout, axial compression ratio, and aspect ratio on columns’ hysteresis behavior, and the hysteresis curves, skeleton curves, failure modes, stiffness degradation, ductility, and energy dissipation capacity were obtained. Results demonstrated the favorable seismic performance of composite columns. Additionally, an increase in chambers led to a full hysteresis curve, enhancing bearing and energy dissipation capacities. The displacement ductility coefficient (μ) ranged between 3.88 and 7.45, and the design parameters have minimal influence on the stiffness degradation of the composite beam. Based on the results, the long and short sides of the CFST columns with a large length–width ratio should be arranged to be relatively close in length.

Integrated absolute full energy peak efficiency: A measure of photon registration efficiency

Integrated absolute full energy peak efficiency (IAFEPE) is a measure of photon registration efficiency using the γ-ray spectrometry method. We have derived appropriate formulas and theoretical explanations of IAFEPE for the first time. IAFEPE is a definite integral (Riemann integral) of the photon registration efficiency function within the detection energy range. IAFEPE, along with associated quantities such as mass integrated absolute full energy peak efficiency and surface integrated absolute full energy peak efficiency, allows for the quantitative validation of measurement conditions.

A Loop Quantum-Corrected Family of Chiral Cosmology Models

We construct and examine a holonomy-corrected chiral fields model of cosmological relevance. Specifically, we holonomize the Hamiltonian corresponding to a quintom field scenario with additional kinetic interaction (governed by the constant chiral metric, mab) on a flat FLRW background and contrast the resulting model with the corresponding purely classical system. In particular, it is shown that the single LQC bouncing stage is ensured to be realized, provided the full chiral kinetic energy function does not change sign during evolution. (As preparation, a particularly simple k-essence field is examined within the effective LQC scheme; some exact solutions are obtained in the process.) Additionally, under the said assumption, it is established that the landmark bouncing mechanism of standard (effective) LQC is still guaranteed to be featured even when taking any finite number of fields ϕ1,…ϕm and mab to be dependent on such fields (the particular zero-potential case corresponding to a family of simple purely kinetic k-essence multi-field cosmology models).

Strategy strengthens structural identification through hyphenating full collision energy ramp-MS2 and full exciting energy ramp-MS3 spectra: An application for metabolites identification of rosmarinic acid

“MS/MS spectrum to structure” analysis is the most challenging task for MS/MS-relied qualitative characterization. The conventional database- and computation-assisted strategies cannot reach confirmative identification, notably for isomers. Hence, an advanced strategy was proposed here through tackling the two determinant obstacles such as the transformation from elemental compositions to fragment ion structures and the linkage style amongst substructures. As typical conjugated structures, esters were measured for strategy illustration, and metabolite identification of a famous natural antioxidant namely rosmarinic acid (RosA) in rat was undertaken for applicability justification. Through programming online energy-resolved (ER)-MS for the first collision cell of Qtrap-MS device, full collision energy ramp (FCER)-MS2 spectrum was configured for [M−H]− ion of each ester to provide optimal collision energies (OCEs) for all concerned diagnostic fragment ions (DFIs), i.e. a-, b-, c-, y-, and z-type ions. The linear correlations between masses and OCEs were built for each ion type to facilitate DFIs recognition from chaotic MS2 spectrum. To identify 1st-generation fragment ions, full exciting energy ramp (FEER)-MS3 spectra were configured for key DFIs via programming the second ER-MS in the latter collision chamber. FEER-MS3 spectrum of 1st-generation fragment ion for ester was demonstrated to be identical with FEER-MS2 spectrum of certain hydrolysis product when sharing the same structure. After applying the advanced strategy to recognize DFIs and identify 1st-generation fragment ions, a total of forty metabolites (M1−M40), resulted from hydrolysis, methylation, sulfation, and glucuronidation, were unambiguously identified for RosA after oral administration. Together, the advanced bottom-up strategy hyphenating FCER-MS2 and FEER-MS3 spectra, is meaningful to strengthen “MS/MS spectrum to structure” analysis through recognizing and identifying fragment ions.

On the symmetry of photon detection arrays: A directionally sensitive 3D model

A detector's ability to obtain the direction of a radioactive source is an invaluable operational asset. A 2D/3D model was developed based on directionally sensitive arrays. The average location of photon interactions within a symmetrical array yields the direction of the source. The model is validated with simulations and laboratory measurements, maximum systematic error being 5–10° at energies >200 keV and approaching zero at lower energies. The symmetry model yields the direction of a shielded source even when no full energy photons could be detected.

A technique for enhancing tight oil recovery by multi-field reconstruction and combined displacement and imbibition

A seepage-geomechanical coupled embedded fracture flow model has been established for multi-field coupled simulation in tight oil reservoirs, revealing the patterns of change in pressure field, seepage field, and stress field after long-term water injection in tight oil reservoirs. Based on this, a technique for enhanced oil recovery (EOR) combining multi-field reconstruction and combination of displacement and imbibition in tight oil reservoirs has been proposed. The study shows that after long-term water flooding for tight oil development, the pressure diffusion range is limited, making it difficult to establish an effective displacement system. The variation in geostress exhibits diversity, with the change in horizontal minimum principal stress being greater than that in horizontal maximum principal stress, and the variation around the injection wells being more significant than that around the production wells. The deflection of geostress direction around injection wells is also large. The technology for EOR through multi-field reconstruction and combination of displacement and imbibition employs water injection wells converted to production and large-scale fracturing techniques to restructure the artificial fracture network system. Through a full lifecycle energy replenishment method of pre-fracturing energy supplementation, energy increase during fracturing, well soaking for energy storage, and combination of displacement and imbibition, it effectively addresses the issue of easy channeling of the injection medium and difficult energy replenishment after large-scale fracturing. By intensifying the imbibition effect through the coordination of multiple wells, it reconstructs the combined system of displacement and imbibition under a complex fracture network, transitioning from avoiding fractures to utilizing them, thereby improving microscopic sweep and oil displacement efficiencies. Field application in Block Yuan 284 of the Huaqing Oilfield in the Ordos Basin has demonstrated that this technology increases the recovery factor by 12 percentage points, enabling large scale and efficient development of tight oil.

Characterization of a Germanium Detector by Means of Experimental Measurements and GEANT4 Monte Carlo Simulations

A HPGe detector was modelled and characterized by means of experimental measurements and Monte Carlo simulations. The simulation based on Monte Carlo GEANT4 was used to characterize the potential dead layer/inactive materials and Full Energy Peak Efficiency (FEPE). The calibration of FEPE for the HPGe detector was conducted in the γ-ray energy range from 88 keV to 1332 keV, using eight standard point sources of gamma radiation: 137Cs, 133Ba, 109Cd, 65Zn, 60Co, 57Co, 54Mn, and 22Na. The efficiency dependence curves were obtained by changing the source to detector distance from 8 cm to 12 cm. a remarkable similarity in FEPE for low energy measurements ranging from 88 keV to 122 keV was obtained between the simulation results and the experimental measurements.

Diamagnetic corrections to low-excited electronic states of light molecular systems

Compact astrophysical objects like white dwarfs and neutron stars generate very strong magnetic fields. In their atmosphere, accretion disks, and the interstellar medium surrounding them, the predominant matter consists of hydrogen, helium and few-particle atoms and molecules. In this work, we have studied the effects of strong magnetic fields on light atomic and molecular systems like hydrogen molecular ions and antiprotonic helium. The full energy of the investigated systems is calculated in the Born-Oppenheimer approximation for a few low-lying electronic states. We investigate the case where the leading effect comes from the quadratic magnetic field term in the interaction Hamiltonian. The electronic energies and wavefunctions are computed in spheroidal coordinates by a finite difference method on a nonequidistant grid. The diamagnetic contributions to the total energy for an arbitrary value of the magnetic field strength are also calculated in perturbation theory. Then they are compared with the exact results, and where possible - with previous calculations. The electronic energy terms could be used for precise computations of the spectral lines of the hydrogen molecular ion and antiprotonic helium. This will allow searching for objects, like neutron stars and white dwarfs with strong magnetic fields, containing such molecular systems in their atmospheres or accretion discs. When the effects from the approximations are taken into account, the tabulated results presented in this work could also find an application in studies for much weaker magnetic field strengths existing in laboratory environments.

Neutron Total Cross Sections of 232Th, 237Np, 235,238U, and 239Pu from 3 to 230 MeV

Neutron total cross-section data for 232Th, 237Np, 235,238U, and 239Pu were measured over the energy range of a few MeV up to 230 MeV at the Weapons Neutron Research Facility of the Los Alamos Neutron Science Center. The results for 235U, 237Np, and 239Pu are the first to be reported over this full energy range. Our data are compared to the ENDF/B-VIII.0 and JENDL-5 evaluations and to selected previous data sets. These results provide neutron cross sections with small statistical uncertainties and low systematic errors to improve theoretical modeling and data evaluation for these nuclei.

Ab Initio Potential Energy Surface for NaCl-H2 with Correct Long-Range Behavior.

We report a full dimensional ab initio potential energy surface for NaCl-H2 based on precise fitting of a large data set of CCSD(T)/aug-cc-pVTZ energies. A major goal of this fit is to describe the very long-range interaction accurately. This is done in this instance via the dipole-quadrupole interaction. The NaCl dipole and the H2 quadrupole are available through previous works over a large range of internuclear distances. We use these to obtain exact effect charges on each atom. Diffusion Monte Carlo calculations are done for the ground vibrational state using the new potential.

Mood States (POMS) Condition Profile Analysis of Senior Women's Cricket Athletes in East Java before The North Aceh Sumatra PON 2024

One factor that could affect an athlete’s mental and emotional readiness is mood. Mood profile for Cricket athletes is an important factor that needs to be analyzed. An athlete’s mood can affect their overall performance. A positive mood can increase focus, motivation,and self-confidence, while a negative mood can hinder an athlete’s abilities and affect desired results. The aim of this research is to determine the condition of the Profile of Mood States (POMS) of East Java Female Senior Cricket Athletes before the 2024 Aceh North Sumatra PON. This research method uses descriptive quantitative research with seventeen athletes as the sample in the research and limited only to East Java Senior Female Cricket Athletes. The results of the research shows that the “Medium” category with the highest percentage is the anger indicator (AMR) at 72.27%, and the confused mood indicator (SSB) at 72.10%. Indicators with a medium percentage include indicators of full energy (PNT), self-assessment (PDR), and depression (DPS) of 70.59%. The percentage of fatigue indicators (KLH) was 69.08% and the indicator with the lowest category was the tension indicator (KTG) at 68.07%. The conclusion of the research on Profile of Mood States (POMS) Condition Analysis for East Java Women’s Senior Cricket Athletes before the 2024 Aceh North Sumatra PON was in “Medium” condition. Negative mood conditions in the “Medium” category such as fatigue, anger, tension, confusion and depression indicate that athletes are not feeling stressed mentally and physically. Meanwhile, positive mood conditions in the “Medium” category make athletes have a good mood, such as being full of energy and self-confidence. This is possible because the training portion is good and the conditions for the 2024 Aceh North Sumatra PON are still quite long. So, there are still many athletes who experience good mood conditions.

Development of a framework to assess the greenhouse gas mitigation potential from the adoption of low-carbon road vehicles in a hydrocarbon-rich region

This study developed a novel assessment framework to analyze long-term energy transition in the road transport sector in which various technology options, market shares, policy measures, costs, and greenhouse gas emissions are considered in a single framework analysis. A data-intensive model was developed with the Low Emissions Analysis Platform (LEAP) and used to analyze policy scenarios up to 2050 for Alberta, Canada, a hydrocarbon-rich province with an emission-intensive energy sector. Three key policy measures – carbon pricing, zero-emission vehicle sales mandate, and incentivization – were analyzed in nine individual and combined policy scenarios. The transition to both hydrogen fuel cell electric vehicles and battery electric vehicles was assessed for all vehicle categories. Each fuel's full energy supply chain was modelled, including resource extraction, conversion, transmission and distribution, and fuelling, allowing for final and primary energy analysis. The findings show that carbon price and zero-emission vehicle incentives do not effectively lower greenhouse gas emissions on their own; zero-emission vehicle mandates are needed to transition the sector to a low-carbon energy system. The system-wide greenhouse gas emission footprints of hydrogen and battery electric vehicles are significantly below conventional vehicles in all cases. Scenarios biased towards battery electric vehicles had the most favorable results. The greenhouse gas emission footprint of hydrogen vehicles supplied by auto-thermal reforming with 91% carbon capture was lower than for battery electric vehicles powered by a primarily natural gas-based power grid. The findings on the effectiveness of carbon prices, incentives, and vehicle mandates should be considered by government policymakers aiming to reduce greenhouse gas emissions, infrastructure planners, and other energy stakeholders.

Coordinated frequency control study of variable speed variable pitch of DFIG load shedding unit based on VSG

The involvement of wind turbines operating at load shedding levels in primary frequency regulation serves as a crucial technical solution to provide high levels of inertial response capability and frequency regulation capability in power systems with significant proportions of renewable energy. Load-shedding units' frequency regulation capacity is constrained by the optimal operating speed, which prevents the utilization of the rotor's full kinetic energy and consequently limits the system's ability to provide strong inertia support. Additionally, the units are restricted by the maximum speed in the medium wind speed range, resulting in a reduced reserve capacity. The control mechanism of virtual synchronous generator (VSG) can ensure voltage stability at the machine end, and enable real-time tracking of the grid frequency, thereby imparting to wind turbines the on-grid operation characteristics of synchronous generator sets. To achieve this goal, this paper proposes a coordinated frequency control method for variable-speed variable-pitch doubly fed induction generator units based on VSG. Differentiated control strategies are employed for varying wind speed ranges, while an additional frequency control module is utilized to realize frequency regulation functionality. In conjunction with VSG, this approach enhances the inertial response of the units and strengthens their ability to support grid frequency. Simulation results indicate that the proposed control method mitigates the rate of decline in grid frequency and reduces frequency deviation, ultimately promoting grid stability. Additionally, a simulation system was designed based on the conventional four-machine two-area model to verify the effectiveness of this approach.

Booster conceptual design of the southern advance photon source

The Southern Advanced Photon Source is a proposed diffraction-limited storage ring operating at middle energy. A candidate injector includes a low energy Linac and a full energy booster. In the paper, we present the concept design of the booster, which is a high intensity synchrotron accelerator. An impedance model has been obtained and the instability threshold has been predicted.

Analysis of changes in cotton moisture under the influence of infrared (IR) radiation

Current cotton drying technology has a negative impact on product quality due to the use of high temperatures and very low energy efficiency. In the literature on the research on their elimination, information on heat generation from fuel by traditional methods and the use of drum dryers is presented, and the above problems have not been completely solved. The article presents the results of research on the possibility of reducing water vapor in cotton under the influence of infrared radiation based on functional ceramics. In this case, as a result of changing the wavelength of radiation, the full energy consumption is based on the evaporation of water in the product. As a result, it was determined that the moisture content of cotton does not have a negative effect on the quality indicators of the fiber, and the appearance of the fiber does not change. Energy efficiency is proven to be high.

Development of Building Design Optimization Methodology: Residential Building Applications

Building design optimization is a highly complex problem, requiring long computational running processes because of the many options that exist when a building is being designed. This paper introduces an integrated approach through which to perform this optimization within an acceptable time frame. The approach includes the methods of variable selection, model simplification, and a sequential optimization process. Using singular value decomposition, a large number of design variables is reduced to a smaller subset that can be solved more quickly through the optimization algorithm. To expedite the variable selection process, a modeling approach that quickly simulates annual energy consumption was developed to replace full annual energy simulations. The developed methodology was applied to two residential buildings in the US, and the results are discussed herein. To assess the accuracy of the integrated optimization methodology, the optimized life cycle costs are compaa variables demonstrating the strongest contributions in the optimization study were identified. The proposed methodology significantly shortened the time requirements for the optimization processes of the two case studies by 74% and 84%; the optimized life cycle costs were within 0.05% and 0.06%, respectively, of the optimum point.