Hot Material Research Articles

Forecasting the performance of a district solar thermal smart network in desert climate – A case study

The present paper investigates the performance of a district solar thermal smart network capable of providing the cooling, heating, and domestic hot water needs for a group of 100 villas in the desert climate of Riyadh, Saudi Arabia. Evacuated tube solar collectors are distributed over the villas’ roofs, while the hot water Lithium Bromide absorption chillers and hot phase change material thermal storage tanks are located in a centralized plant. Electrical heating elements embedded in the thermal storage tanks are considered as back up auxiliary sources in case of shortages. Using the “Design Builder” energy simulation program, a typical villa constructed as per the local thermal standard has been modeled to calculate the hourly thermal loads. These hourly profiles are the initial inputs for a Transient System Simulation (TRNSYS) model integrated with the Generic Optimization Program (GenOpt). The interaction between these two programs is used to find the optimized sizing of the solar collectors’ area and the hot thermal storage volume which could achieve the maximum thermo-economic performance with a 100% solar fraction. The hourly transient simulations over a one-year period show that this system can achieve up to 82.67% reduction in the annual electrical consumption as well as carbon dioxide emissions if compared to conventional district thermal plants. Furthermore, the smart network benefits have been revealed from three different aspects: generation source, transmission loop network, and end-user consumer. The feasibility analysis performed shows that adopting the smart network can enhance the profitability of the project by 34.89% if compared to central solar plants. Also, it gives the end-user the opportunity to participate in energy production through buying the solar collectors installed on their roofs, and thus further enhancing the reduction in their annual thermal bills from 23.13% to 82.88% in a payback period of 4 years and 11 months.

Deep origin of Cenozoic volcanoes in Northeast China revealed by 3-D electrical structure

The three-dimensional (3-D) electrical structure of the upper-mantle was used to examine the deep origins of and relationship among the Cenozoic volcanoes located in Northeast China (NEC). High-quality, long-period magnetotelluric (LMT) full-impedance tensor data were collected in NEC and subjected to 3-D Gauss-Newton inversion in order to construct a resistivity model. The resulting model reveals the presence of multiple localized low-resistivity anomalies (LRAs) within the high resistivity lithosphere beneath NEC. These LRAs partially coincide with Cenozoic volcanoes on the surface. Three LRAs that form a larger, annular LRA were observed in the deep upper mantle beneath the Songliao Basin, whereas vein-like LRAs were found in the asthenosphere that connect the lithosphere and deep upper mantle. Petrophysical analyses suggest that the LRAs may have been caused by fluid-induced melting. Based on our electrical model, we propose that, following dehydration of the subducted Western Pacific slab into the mantle transition zone (MTZ) beneath NEC, the released water migrated upward and caused partial melting at the top of the MTZ beneath the Songliao Basin. Under the effect of buoyancy, the melted mantle formed a thermal upwelling that caused melting of asthenosphere before diapiring at the base of the dry lithosphere. The magma then penetrated structural boundaries (such as thinner, weaker, or activated suture zones) and finally reached the Earth’s surface. This melting and upwelling of hot mantle materials may have resulted in large-scale volcanism in the region throughout the Cenozoic, including the eruption of Changbai Mountain and Halaha Volcanoes. Our results suggest that the Cenozoic NEC volcanoes may all share a similar mode of genesis, and probably originated from the annular LRA in the deep upper mantle.

Insight into picosecond kinetics of insulator surface under ionizing radiation

We found experimentally and theoretically that MgO, CaF2, and Y3Al5O12 (YAG) irradiated with fast ions demonstrate a noticeably different surface response. Striking differences follow from the kinetics of nanodroplets ejection. Protrusion of the hot materials and subsequent recrystallization in MgO and CaF2 recover transient damage in the surface region, forming a spherically shaped nanohillock. YAG demonstrated almost no recovery of the transient disorder, forming an amorphous hillock. These differences are attributed to complex interplay between the mobilities of atoms in the hot region and surface tensions.

Complex Deformation of Central and North China Through Pn Velocity and Anisotropy Tomography

AbstractUsing our recently developed Pn tomography method, we obtain high‐resolution Pn velocity and anisotropy structures of uppermost mantle beneath the Central and North China, which provide useful insight concerning the mechanism of intraplate mantle dynamics. The consistency between the new Pn model and seismic reflection/refraction profiles demonstrates the high quality of our model. Based on the Pn anisotropy structure surrounding the Alxa Block, we infer that material extrusion from northeastern Tibet was impeded and turned to the west and south edges of the Alxa Block. The Pn structures beneath the Sichuan Basin and Songpan‐Ganzi Orogen suggest that the stable Sichuan Basin impeded material extrusion from the Tibetan Plateau and caused material from Tibet to be extruded separately along the west and northwest edges of the Sichuan Basin. To the north of the Sichuan Basin, we infer that the extrusion has ceased within the Songpan‐Ganzi Orogen rather than to further east. The high Pn velocities beneath the Qinling Orogen do not support the proposal of large‐scale eastward material escaping flow in the shallow mantle beneath the western Qinling Orogen. The Pn velocity distribution beneath the North China Craton indicates that hot material from the mantle is more likely to upwell beneath deep faults or active orogenic areas. Our model indicates that the northern and central parts of the Ordos Block retain stable structures at the uppermost mantle, while its southeastern has been reworked by hot material.

Strain-induced band modulation and excellent stability, transport and optical properties of penta-MP2 (M = Ni, Pd, and Pt) monolayers.

First principle calculations utilizing density functional theory were carried out to investigate the electronic, transport and optical properties of penta-MP2 (M = Ni, Pd and Pt) monolayer compounds under applied uniaxial and biaxial tensile strains. With an optimum magnitude of applied strain, we found band gap transitions in penta-MP2 monolayers from zero/narrow to the semiconductor regime, wherein band gaps were noticed to be firmly dependent on the applied uniaxial and biaxial tensile strains. In this study, the PBE approach was used primarily to evaluate electronic properties, from where the identified architectures of penta-MP2 with maximum obtained bandgaps under respective optimum strains were assessed through the HSE06 method of calculation for better estimation of band gaps and optical properties. Prior to HSE calculations, we affirmed our assessment for the stability and reliability of the compounds under uniaxial and biaxial strains of up to 15% through phonon spectrum and elastic calculations. A distinct transition was also noted from semiconductor to metal for all compounds after the applied optimum uniaxial and biaxial strains. The optical absorption spectra in all the stretched penta-MP2 compounds reached the order of 106 cm−1, with significant peaks belonging to the IR and visible regions; this indicates promising applications of these materials in high-performance solar energy and good hot mirror materials. The enhanced I–V responses under uniaxial and biaxial tensile strains using the non-equilibrium Green's function (NEGF) approach confirm the usefulness of the strained state of the considered penta-MP2 monolayers. The results show that tuning electronic properties, I–V characteristics and optical properties of stretched penta-MP2 compounds under tensile strain merits significant future applications in optoelectronic devices and as good hot mirror materials.

Influence of cold and hot rolling on the corrosion behaviour of duplex stainless steels in mine water environment

This study examined the corrosion behaviour of cold and hot rolled duplex stainless steel materials in mine water. Both gravimetric and electrochemical methods (potentiodynamic polarisation and open circuit potential) were adopted to monitor the corrosion of the alloys. Microscopy analyses were used to understand the degradation phenomena. In comparison, cold-rolled stainless steels displayed better resistance than hot-rolled materials under the tested conditions. The mine water pH was in the range that could lead to passivation of the sample and hence, the environmental impact was not aggressive enough to create many inferences. The surface deteriorations for cold and hot rolled steel materials were therefore not severe in both SEM (Scanning Electron Microscope) and OM (Optical Microscope) analysis results.

Design of Smooth Aluminum Bonded Sheaths in HV XLPE Cables Based on the Bending Performance Research

In China, recent ablation failures of water-blocking buffer layer occurred in high voltage (HV) cross-linked polyethylene (XLPE) cables with corrugated aluminum sheath have stimulated the product development of cables with smooth aluminum bonded sheath. Despite the many advantages, bending performance is one of the few weaknesses of smooth aluminum bonded sheath. In this paper, a three-dimensional model of a cable with smooth aluminum bonded sheath in a four-point bending test was set up, where the cohesive zone model was applied to simulate the mechanical behavior of the adhesive layer (bonding interface). The influence on the bending performance of the bonded sheath by the thickness of aluminum layer, the parameters of hot melt adhesive, the thickness and material parameters of outer jacket, as well as the cable specification was investigated, together with the stress distribution and damage analysis of the adhesive layer. Based on the research, the material selection and structural design of smooth aluminum bonded sheath were recommended for HV XLPE cables, including an additional requirement for the shear strength of hot melt adhesive besides those already in IEC and IEEE standards. Finally, a 110 kV XLPE cable with smooth aluminum bonded sheath was manufactured and type tested.

Comparative Evaluation of Moisture Susceptibility Test Methods for Routine Usage in Asphalt Mixture Design

Abstract Asphalt materials experience substantial amounts of environmental damage throughout their lives as surface layers in pavements. One of the most prominent forms of environmental damage, moisture-induced damage, is caused by the weakening of internal bonds of the material because of the presence of moisture in the voids of asphalt mixtures and is a common problem for asphalt pavements in wet climates. Moisture-induced damage is typically accounted for during asphalt mixture design by conducting performance tests to ensure the material is not susceptible to severe damage from moisture, although many of these methods have seen mixed amounts of success historically. The main objective of this study is to evaluate the ability of multiple asphalt mixture moisture susceptibility tests to identify good and poor performing mixtures with respect to moisture-induced damage to replace current mix design testing requirements. Ten plant-produced hot mix asphalt materials with established good and poor field moisture performance were subjected to various moisture susceptibility test methods. The results from these procedures are assessed to determine which procedure is most effective and practical as a moisture susceptibility test for routine usage during asphalt mixture design for transportation agencies. Results from this study suggest that performance tests with stiffness-based measurements, such as dynamic modulus paired with moisture conditioning and the saturated aging tensile stiffness procedure, show better correlation to field performance than traditional test methods such as AASHTO T-283, Standard Method of Test for Resistance of Compacted Asphalt Mixtures to Moisture-Induced Damage, and that the Hamburg wheel tracker test is the most effective and practical test method to reliably identify mixtures prone to experiencing moisture-induced damage.

The Present-Day Crustal 3D Movement and Geodynamic Mechanisms in Hainan Island

The characteristics of the present-day crustal three dimensional (3D) movement with GNSS data during 1999-2018 and the precise leveling data during 1970s-2018 in Hainan Island and its adjacent area are analyzed. Based on the data and the horizontal movement field in the region of Southeast Asia, we discuss how the horizontal velocities in Hainan and the continental margin of the South China block (SCB) are affected by the Eurasian plate, the India-Australia plate and the Philippine Sea plate. The results show the movement of Hainan Island is the same as SCB. The horizontal velocities of the continental margin in South China are different in the east and the west along the boundary of the Northeastern Coast block and Yangtze Block. In Hainan Island, the 3D movement is different in two regions divided by Baisha fault. The movement of SCB is affected by Indo-European collision and extrusion. The movement of the continental margin is affected by both the Pacific Ocean plate, the Philippine Sea plate, the expansion of the South China Sea (SCS), the hot materials underplating and subsequent lithospheric extension. The effect on the regional movement by the Australia plate is smaller, but it can cause co-seismic step to SCB when there had a giant earthquake in Sumatra which is caused by the convergence of the Australia with the Sunda Plate in the NE direction.

LINEAR FRICTION WELDING – PROCESS CONTROL AND MACHINE TECHNOLOGY

Linear Friction Welding (LFW) is well adapted to produce titanium aircraft engine and structure parts, as an alternative to machining from solid, from forging or from electron beam welded blanks. The process can be described through a small number of mechanical variables: the amplitude and frequency of oscillation motion, the contact pressure and the axial displacement resulting of hot material flowing outside of the joint interface. Nonetheless, because of the high speeds and loads, the correct control and monitoring of linear friction welding requires special care on machine and tooling design. The main principles of LFW machine design are described, with a special focus on the consistency between process quality requirements and machine characteristics: the static and dynamic machine behavior, the control system performance, the sensor technology and the tooling clamping solutions shall allow a good control of the weld parameters and an accurate monitoring of the physical phenomena at the joint interface.

Lime binders for the repair of historic buildings: Considerations for CO2 abatement

Abstract Lime binders are utilised worldwide and are associated with a considerable scale of production and corresponding CO2 emissions. The relevance of this review is therefore international in scope, with production transcending geographical boundaries and construction practices. An holistic view of lime binders, considering their provenance, production and utilisation offers the potential for significant CO2 savings urgently required globally. Importantly, the technical aspects of lime materials production is critical, but the alteration of behaviour of both specifier and those undertaking the construction processes is also essential in achieving meaningful CO2 emission reduction. This review paper investigates the life cycle stages of lime binders in line with the features highlighted in the Scottish Building Alliance (SBA) ‘building life cycle stages model’. It attempts to determine what can be learnt from our understanding of the manufacture and use of binders from historic, current and future perspectives in the context of reconciling the production of historically authentic materials in a decarbonising environment. The production and use of such authentic historic lime binders initially appears highly carbon intensive through its utilisation of relatively inefficient kiln technologies and loss of economies of scale associated with larger operations. However, this review shows numerous benefits in the production of such binders; including their CO2 sequestration capability, lower potential processing energy, and a reduction in excessive ‘carbon miles’ associated with transportation. Importantly, we show how historic production and on-site manufacture approaches with lime-based materials also offers exciting potential for carbon savings. Importantly, hot mixed lime mortars offer the promise of higher durability materials compared to their modern cold manufactured counterparts, thereby reducing the frequency of repeat maintenance interventions, again yielding CO2 savings. We suggest hot mixing, whether in an innovative contemporary materials realm or within traditional contexts should be explored. In addition, hot mixed materials can concomitantly satisfy conservation requirements for repairs through better reflecting the aspired to building conservation requirement of like for like materials replacement reflected with historically produced binders. We suggest future paths for the industry that would simultaneously reconcile demands for authentic materials and production methods for the conservation sector with the necessity of achieving cleaner production in a decarbonizing world.

The Effect of Hot Working on the Mechanical Properties of High Strength Biomedical Ti-Nb-Ta-Zr-O Alloy.

Beta titanium alloy Ti-35Nb-6Ta-7Zr-0.7O (wt%) was developed as a material intended for the manufacturing of a stem of a hip joint replacement. This alloy contains only biocompatible elements and possesses a very high yield strength already in the cast condition (900 MPa). However, the porosity, large grain size and chemical inhomogeneity reduce the fatigue performance below the limits required for utilization in the desired application. Two methods of hot working, die forging and hot rolling, were used for processing of this alloy. Microstructural evolution, tensile properties and fatigue performance of the hot worked material were investigated and compared to the cast material. Microstructural observations revealed that porosity is removed in all hot-worked conditions and the grain size is significantly reduced when the area reduction exceeds 70%. Static tensile properties were improved by both processing methods and ultimate tensile strength (UTS) of 1200 MPa was achieved. Fatigue results were more reproducible in the hot rolled material due to better microstructural homogeneity, but forging leads to an improved fatigue performance. Fatigue limit of 400 MPa was achieved in the die-forged condition after 70% of area reduction and in the hot rolled condition after 86% of area reduction.

Insightful Analysis and Targeting of the Optimal Hot Feed toward Energy Saving

Feed of hot material from the upstream process is a strategy to improve energy efficiency, but the energy saving contributed by hot feed depends on the characteristics of the feed stream and receiv...

Determination of biofilm forming activity of microorganisms on synthetic polymeric materials.

Microorganisms are able to form biofilms on surfaces of biotic and abiotic nature. In turn, in human biotopes there are optimal conditions for the implementation of biofilm-forming activity. Moreover, in medical practice, polymeric materials are often used for drainage or prosthetics, which can also be successfully colonized by bacteria. However, in laboratory practice, the formation of biofilms is usually evaluated on glass or polystyrene. The purpose of the study is to evaluate the methodological features of studying the biofilm-forming activity of microorganisms on the surface of synthetic polymeric materials. We used strains of Staphylococcus aureus ATCC 25923, Escherichia coli K-12, Candida albicans ATCC 10231, as well as synthetic polymeric materials - DentLight Flow light-curing composite material (nano-hybrid fluid composite; Russia), glass ionomer chemical curing Fuji 1 (Japan), cement for temporary fixation of orthopedic constructions TempBond NE (USA), acrylic, polyurethane and polyvinyl chloride. The formation of biofilms in flat-bottomed ELISA plates in this study was considered as a control group. If the polymer belonged to cold curing materials, sterile flat-bottomed tablets were used, the bottom of which was filled with a thin layer of plastic. After hardening of the plastic, biofilms were formed in the tablets. In the second series of experiments, hot cured materials cut into equal parts 5×5×1 mm in size were placed in the wells of a plate and again used to determine biofilm formation with subsequent coloring. To extract the dye, the pieces were transferred to a new plate to exclude the amount of film biomass formed on the walls of the plate wells. In both cases, cultivation was carried out at 37° C for 24-48 hours. The biomass of the film was stained with fuchsin. Statistical data processing was performed using t-Student criterion. For the threshold level of significance, the value p <0.05 was taken. It is established that the proposed options for determining biofilm forming ability are available and indicative. It was revealed that the same microorganisms have individual biofilm formation indicators for each polymer material. The light curing dental composite and polyvinyl chloride exhibit the more pronounced antiadhesive properties than cements and polyurethane. Up to date, most of the studies of biofilm formation have been carried out using glass or polystyrene, which, as a rule, are not used for the manufacture of prostheses, catheters, drains, etc., which makes it difficult to assess the true film-forming activity of microorganisms. The proposed methodological approaches, especially the second option for preparing testing samples, solve this problem. In general, the proposed approaches to testing biofilm-forming activity on polymers are very simple to implement and generally available. For an adequate study of the biofilms formation, it will be advisable to use polymer materials, directly used in medicine, rather than polystyrene tablets, the material of which is found exclusively in laboratory practice.

Структура и жаропрочность интерметаллидного ренийсодержащего сплава после термической обработки

The developed intermetallic Ni3Al compound-based alloys, known under the VKNA (ВКНА) and VIN (ВИН) brands, attract attention due to high operating temperatures --- up to 1200 °C, and relatively low density --- ~ 8 g / cm3. The first-generation intermetallic alloys such as VKNA-1V (ВКНА-1В) and VKNA-4U (ВКНА-4У) are known not to require multi-stage heat treatment. An increase in the strength characteristics caused by high requirements for the hot gas path materials also occurs due to an increase of high-melt alloying elements. Therefore, investigations in the field of temperature effects on the structure and properties of new generation intermetallic alloys become very relevant. In our research we studied the influence of heat treatment on the structural phase state of the VIN4 (ВИН4) intermetallic alloy containing rhenium. Findings show that annealing at close to solvus temperatures allows increasing the time to failure during 1100 °C stress-rupture strength tests. At the same time, during the heat treatment of the alloy with a high cooling rate, elements are redistributed with uneven allocation of phases of different morphology enriched in molybdenum and chromium, which negatively affects the results of stress- rupture strength. The research is an intermediate step in establishing patterns of influence of heat treatment parameters on intermetallic alloys depending on the degree of alloying.

Full Spectrum Solar Thermal Energy Harvesting and Storage by a Molecular and Phase-Change Hybrid Material

Summary Efficient solar thermal energy harvesting and storage are critical steps toward utilizing the abundant solar irradiation that reaches the surface of the earth. Current solar thermal approaches rely on costly high optical concentration systems, leading to high heat losses by hot bulk materials and surfaces. At the same time, the energy stored in the form of thermal energy has inherently large temporal losses. Here, we combine the physics of molecular energy and latent heat storage to introduce an integrated, simultaneous harvesting and storage hybrid paradigm for potential 24/7 energy delivery. The hybrid paradigm utilizes heat localization during the day to provide a harvesting efficiency of 73% at small scale and ∼90% at large scale. Remarkably, at night, the stored energy by the hybrid system is recovered with an efficiency of 80% and at a higher temperature than that of the day, in contrast to all of the state-of-the-art systems.

Determination of Hypocentre and Seismic Velocity Structure in Guntur Volcano Using Seismic Data from 2010 to 2014

DOI: 10.17014/ijog.6.3.279-289Guntur Volcano was in a dormant state even though its seismicity had increased on April, 2013 and August, 2013. In this study, determination of hypocentre and seismic velocity structure was conducted using seismic data from 2010 to 2014 as recorded by a seismic station of the Centre for Volcanology and Geological Hazard Mitigation of Indonesia (CVGHM). Volcano-Tectonic (VT) earthquakes were identified and carefully picked for P-and S-wave arrival times. More than 600 events of VT earthquakes from 2010 - 2014 were located using maximum likelihood estimation algorithm. The initial 1-D seismic velocity was calculated using Velest method in order to get the initial velocity as the input for the tomographic inversion. The results show distribution of VT hypocentres were clustered in three regions, namely Guntur Volcano, Kamojang geothermal area, and Darajat geothermal area. At the Guntur Volcano region, the VT events were located mostly at the northern part of the crater with the depth of hypocentre ranges from 0 - 4 km. The distribution of the VT events made alignment from the southwest to the northeast with the depth of hypocentre mostly ranges from 0 - 2 km at Kamojang region. Meanwhile, at Darajat geothermal area, the VT events were located at the depth of 0 - 2 km and made alignment from the southeast to the northwest. The low velocity zone associated with hot material or fluids was located at the depth of 5 km beneath the Guntur Crater. The location of VT earthquakes at the depth of 0 - 4 km beneath Guntur Crater was coincided with the area with high Vp and Vs anomalies. The low velocity zones were also found at Kamojang Crater and Cipanas hotspring area. It was predicted that the low velocity zone at the Kamojang Crater was related to a high temperature of the vapour system, whereas the reservoir of water was preferred to be dominated at the Cipanas hotspring.

УДОСКОНАЛЕННЯ КОНСТРУКЦІЇ ХОЛОДИЛЬНИКА КОЛОСНИКОВОГО З МЕТОЮ ПІДВИЩЕННЯ ЗНОСОСТІЙКОСТІ КОЛОСНИКІВ

The article discusses one of the ways to improve the design of the grate refrigerator in order to increase the wear resistance of grate. Typically, the life of the grate is reduced when a certain amount of wear is exceeded, it is expressed in a decrease in the thickness of the elements and walls of the grate, which undergo oxidation and abrasion due to the movement of the cooled material. As a result, the grate ceases to function properly. In connection with that, there is proposed an improved grate design, in which: we have a contour of the bottom surface of the cavity in an inclined grate plate, made with an inclination growing in a direction opposite to the direction of movement of the cooled material. The grates are made with the ledges in an inclined plate of a triangular shape, also with reinforcing stiffening ribs of arched shape between the passages for cooling air. This will create a permanent protective layer of chilled material and will reduce the surface area of the grate while cooling the clinker in the grate refrigerator, which will increase the strength and lifespan of the grate and will accelerate the cooling of hot material.

Low-velocity layers in the northwestern margin of the South China Sea: Evidence from receiver functions of ocean-bottom seismometer data

The receiver function method was applied to teleseismic recordings of an active-source ocean-bottom seismometer array in the northwestern margin of the South China Sea. Forward modeling of the receiver functions was used to derive velocity interfaces beneath the stations. Two main groups of low-velocity layers were imaged. The first group in the reef area, with a thickness of 7–10 km, exhibits a seaward uptrend of the buried depth but poor continuity. The second group, with a thickness of 3–4 km, is more continuous along the Zhongsha Trough; the buried depth decreases asymmetrically from the flanks to the rift center. A high shear wave velocity layer of ~4.0 km/s is imaged at the crust bottom beneath the Zhongsha Trough, with thickness of ~3 km. The average Vp/Vs in the Cenozoic sediment is 2.0–3.0 and was affected by high fluid activity induced by intensive faults. The Vp/Vs of the crust varies between 1.77 and 1.88, suggesting an intermediate to basic composition under the continental extension. Together, these results suggest a two-stage evolution model of the continental crust. In the first stage, the crust deformed in a ductile manner and thus created considerable shearing structures with high anisotropy that caused the obvious decrease of the shear wave velocity. In the second stage, the shearing structures connected asymmetrically, driven by detachment faults in the upper crust and upwelling of the lower crust. The Zhongsha Trough then formed, probably with magmatic underplating due to lithospheric extension or rising of hot mantle materials.

Fine Modulation of the Higher-Order Excitonic States toward More Efficient Conversion from Upper-Level Triplet to Singlet.

Hot exciton luminogens capable of harvesting nonemissive triplet excitons via reverse intersystem crossing from high-order triplet (hRISC) to singlet have great potential in high-efficiency fluorescent organic light-emitting diodes (OLEDs). Although spin-orbit coupling (SOC) is regarded as a key factor affecting the RISC process, its effects on hot exciton materials are poorly understood. Herein, we design and synthesize two blue-emitting hot exciton luminogens, PABP and PAIDO, to study this issue by modulating the excited-state properties. Theoretical and experimental research contributions demonstrate that a stronger SOC between energetically close S1 (π-π*) and Tn (T3, n-π*) of PAIDO gives rise to faster and more efficient hRISC in comparison to that of PABP, leading to a higher external quantum efficiency and a higher exciton utilization efficiency. Crucially, the experimentally measured hRISC rate (khRISC) of hot exciton materials is on the order of 107 s-1, which is much faster than that of the thermally activated delayed fluorescence materials.