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Fouling and frosting of the outdoor coil in an air source heat pump (ASHP) unit are common but undesirable operating problems. At an increased level of air pollution, fouling of an outdoor coil becomes increasingly severe during its space cooling operation in summer and may potentially impact its frosting operation in winter. This paper reports on a field study on the operating performances of a space heating ASHP unit with a foul outdoor coil as a result of a prolonged cooling operation. Firstly, a detailed description of the field ASHP unit with the foul outdoor coil and test cases is given. Secondly, field study results for the test cases and their analyses are presented. The results demonstrate that fouling of an outdoor coil during its space cooling operation in summer can significantly impact its frosting performance during its space heating operation in winter. [ABSTRACT FROM AUTHOR]

Defrosting under unnecessary conditions is a typical and undesirable operating phenomenon for air source heat pump (ASHP). This paper aims to evaluate the ASHP performance under unnecessary defrosting phenomena in different regions of China. Firstly, energy loss for two kinds of unnecessary defrosting phenomena was quantified by 60 days field test. Secondly, a method was developed to predict unnecessary defrosting times. The prediction accuracy can be controlled within 10%. Furthermore, the ASHP performance of unnecessary defrosting was evaluated for nine typical cities in China. It was found that the average unnecessary defrosting rate was 53% for northern cities, 38% for mid-land cities, and 15% for southern cities during a heating season. Correspondingly, the total energy loss was 233 MJkW −1 , 161 MJkW −1 , and 44 MJkW −1 . These results indicate that unnecessary defrosting processes should not have been ignored. It is a valuable work to improve the defrosting control method. [ABSTRACT FROM AUTHOR]

Pores and throats are the key parameters for determining the pore structure and fluid flow behavior in tight sandstone reservoirs. In this paper, pores and throats of the tight sandstone reservoir of the Upper Triassic Xujiahe Formation in the northern Sichuan Basin were investigated using classical petrography, scanning electron microscopy, and confocal laser scanning microscopy. In addition, a method of pore as well as throat identification and quantitatification using high-pressure mercury injection (HPMI) measurements was worked out. The results show that clay mineral-related pores are well developed in lithic sandstone and feldspathic lithic sandstone in addition to pores produced by dissolution of calcite cement and clastic grains. Intergranular pores are connected by lamellar, curved lamellar, and narrow pore throats. The pores and throats associated with intragranular dissolution and clay minerals are mostly tube shaped. The rapid-increasing and slow-increasing profiles of the mercury injection curves represent the dominance of pores and throats, respectively, allowing to differentiate pores and throats. Calculations show, in addition to fractured lithic sandstone, that has micron-sized pore–throat systems, the other lithic sandstones possess dominatly nano-sized pore–throat systems. In case of feldspathic lithic sandstones, micron-sized and nano-sized pore throat systems are equally important. In micron-sized pore throat dominated reservoirs, the pore volume is slightly larger than the throat volume, whereas for the nano-sized pore throat system, the pore volume is considerably larger than the throat volume. The key factors that are favorable for the formation of lithic sandstone pore throat systems are early calcite dissolution, lithic fragments dissolution, and early chlorite cementation. In contrast the key factors that are favorable for the formation of feldspathic lithic sandstone pore throat systems are dissolution of feldspars and lithic fragments. • A new method to distinguish pores and throats within tight sandstone reservoirs is proposed. • Lithic and feldspathic lithic sandstone reservoirs host different pore and throat types. • Pore volume is slightly larger than throat volume in the micron-size pore network. • Pore volume is considerably larger than throat volume in the nano-size pore network. • Compaction, cementation, and dissolution directly affected the development of pore throat systems. [ABSTRACT FROM AUTHOR]

Pore structure is the key factor to control the quality and fluid flow of ultra-tight reservoir. The relationship between rock types, pore types, and pore sizes of ultra-tight sandstone reservoirs was identified by observing microscopic characteristics under a polarizing microscope and scanning electron microscope (SEM) and quantitively assessed using high-pressure mercury intrusion (HPMI) and fractal theory. By a comparative analysis of lithic sandstone and feldspar lithic sandstone reservoirs of Upper Triassic Xujiahe Formation of the Northern Sichuan Basin, we found that the pore type of the ultra-tight sandstone reservoir was linked to the rock type. Argillaceous lithic sandstone minly generates fracture pores, while fine-grained lithic sandstone and feldspar lithic sandstone formed dissolved pores by dissolution of carbonate cement, rock debris, and feldspar particles. Meanwhile, clay minerals such as kaolinite and chlorite in the reservoir possess pores between clay platelets and intraplatelet pores within clay aggregates, which are important pore types for ultra–tight sandstone reservoirs. A method to divided intervals of pore size distribution was proposed using high-pressure mercury intrusion (HPMI), and three intervals of pore diameter distribution were observed: 10–40 nm, 40 nm–1 μm, and 1–100 μm, which is largely controlled by pore type. The reservoir with only fracture pores is a one–interval reservoir with pore diameter in the range of 1–100 μm, while the reservoirs with dissolved pores and clay mineral-related pores have the above three intervals. Meanwhile, the fractal of pores in different scale range is different, and the larger the pore size, the stronger is the reservoir heterogeneity. A treelike pore structure model can be utilized to define pore development features in ultra–tight sandstone reservoirs. Micron–scale pores with diameters of 1–100 μm is mostly made up of fractures, cement and particle dissolution pores. However, nano–scale pores in the range of 40 nm–1 μm and 10–40 nm are predominantly pores formed between clay platelets and intraplatelet pores within clay aggregates, respectively. • Rock type, pore type, and pore size of ultra-tight sandstone reservoirs have a close relationship. • Pores between clay platelets and pores within clay aggregates are essential pore types in ultra-tight sandstones. • Three intervals of pore distribution were divided using high-pressure mercury intrusion (HPMI). • The heterogeneity of pores in ultra-tight reservoirs is mostly dictated by pore size and fractures. [ABSTRACT FROM AUTHOR]

Based on a thermal pressure simulation experiment under formation conditions, we found that hydrocarbon generation in organic-rich shales can result in extreme overpressure, and that the key factor controlling such overpressure is gas rather than oil. Our experiment was conducted under formation conditions using organic-rich shale samples from the Upper Triassic Chang 7 member of the southern of Ordos Basin with the goal of exploring the overpressure caused by hydrocarbon generation. The results showed that hydrothermal pressures at 73–130 °C ranged from 5.6 to 49 MPa, while those at simulated temperatures of 300–425 °C and vitrinite reflectances of 0.71–1.99% ranged from 23.5 to 116.1 MPa when the system was completely closed. The weights of oil and gas generated in every stage of the experiment were similar, but the volume of gas was up to 1720 times greater than that of oil. The correlation between the volume of oil generated and hydrocarbon generation pressure was poor, but the increased volumes of oil-associated gas during the oil generation stage and gas in the gas generation stage were strongly and positively correlated with hydrocarbon generation pressure. Therefore, gas was the main factor controlling hydrocarbon generation pressures in this study. Higher pressures can exceed the fracture pressures of rocks, resulting in the formation of fractures and leading to the expulsion of oil and gas. The overpressure of a source rock can be transferred into a tight reservoir to become the main driving force for tight oil charging. When the overpressure exceeds 15 MPa, the oil in a reservoir can be charged into <5-nm pore throats, which is important for predicting tight oil potential. • Thermal pressure simulation experiments were conducted under formation conditions. • Hydrothermal and hydrocarbon-induced overpressures reached 49 and 116.1 MPa. • Gas generation in different stages controls hydrocarbon generation pressures. • Tight oil can be charged into <5-nm pore throats when overpressure >15 MPa. [ABSTRACT FROM AUTHOR]

Experimental studies have shown that β-caryophyllene (BCP) improved neurological deficits of cerebral ischemia-reperfusion injury (CIRI) rats resulting from Middle Cerebral Artery Occlusion (MCAO). However, research on targets of BCP on CIRI has not been completed. In this study, the mRNA sequencing was used to distinguish various therapeutic multiple targets of BCP on CIRI. Differentially expressed genes (DEGs) were identified from RNA-seq analysis. CIRI induced up-regulated genes (CIRI vs. Sham) and BCP -induced down-regulated genes (BCP vs CIRI) were identified. Significant DEGs were identified only that expressed in each of all samples. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis of significant DEGs were determined by cluster Profiler. Protein interactive network (PPI) was analyzed using the String tool and Hub genes was identified by cytoHubba. Transcription factor (TF) regulatory network for the potential Hub genes was constructed. Western blot and ELISA were used to verified hub genes and relative inflammatory cytokines. After mRNA sequencing, a total of 411 DEGs were filtered based on the 2 series (CIRI vs. Sham and CIRI vs. BCP), with Pax1, Cxcl3 and Ccl20 are the most remarkable ones reversed by BCP. GO analysis was represented by DEGs involved in multiple biological process such as extra-cellular matrix organization, leukocyte migration, regulation of angiogenesis, reactive oxygen species metabolic process, etc. KEGG analysis showed that DEGs participated several signaling pathways including MAPK signaling pathway (rno04010), Cytokine-cytokine receptor interaction (rno04060), JAK-STAT signaling pathway (rno04630), and others. The protein-protein interaction (PPI) network consisted of 339 nodes and 1945 connections, and top ten Hub genes were identified by cytoHubba such as TIMP1, MMP-9, and STAT3. Subsequently, a TFs-miRNAs-targets regulatory network was established, involving 6 TFs, 5 miRNAs, and 10 hub genes, consisting of several regulated models such as Brd4 - rno-let-7e - Mmp9, Brd4 - rno-let-7i - Stat3, and Hnf4a- rno-let-7b -Timp1. Finally, western blot demonstrated that BCP could inhibit the increased TIMP1, MMP-9 and STAT3 expression in rat brains after I/R. ELISA represented that BCP could suppress inflammatory cytokines caused by CIRI and present anti-oxidative property. In conclusion, this study shows that the intervention of BCP can significantly reduce neurologic deficit, improve the cerebral ischemia, and a total of ten hub genes were found closely related to the treatment of BCP on CIRI. Prudent experimental validation suggests that the BCP might have the neuro-protective effects in CIRI by decreasing the expression of MMP-9 and TIMP-1, STAT3. In a sense, this study reveals that the MMP-9/TIMP-1 signaling pathway may be involved in the injury after CIRI and thus provides a new treatment strategy as well as a researching method for stroke. [ABSTRACT FROM AUTHOR]

The distribution, origin, and evolution of overpressure in the petroliferous basin are important problems that need to be addressed for oil and gas exploration. The distribution and origin of overpressure in the Shahejie Formation in the northern Dongpu Depression are analyzed based on geological studies, logs, and pressure data. The contribution ratios of different overpressure origins are quantified, and the evolutionary stages of overpressures of different origins are further divided. The results show that the formation pressure coefficients of Shahejie Formation in the Dongpu Depression are mainly within the range of 0.9–1.5. The overpressures are mainly distributed in the Sha-3 and Sha-4 Members of the Haitongji sag, the Central uplift belt and the Qianliyuan sag. From the sag to its surrounding area, the formation pressure coefficient gradually decreases. The high deposition rate and strong hydrocarbon generation are the main causes of overpressure formation in the Shahejie Formation in the Dongpu Depression. Based on the stress–strain characteristics of different origin overpressures and the log response parameters, two models, acoustic travel time-effective vertical stress and electrical resistivity-effective vertical stress, are established to identify and quantify the different origin overpressures. The calculation results for the area from the Haitongji sag and Qianliyuan sag to the Central uplift belt show that the main cause of overpressure gradually changes from both disequilibrium compaction and hydrocarbon generation to disequilibrium compaction as the main factor, with the contribution of disequilibrium compaction to overpressure in the Central uplift belt at about 87%. The Sha-3 Members of the Shahejie Formation in the Haitongji sag and the Qianliyuan sag are more strongly affected by hydrocarbon generation, which accounts for 42% and 47.5% of overpressure origin, respectively. There are five stages in the evolution of overpressure in the Shahejie Formation in the northern Dongpu Depression: normal compaction (before 35 Ma), mixed pressurization (35-27 Ma), uplift and pressure release (27-17 Ma), disequilibrium compaction (17-11 Ma), and secondary mixed pressurization (12 Ma-present). • Overpressure mainly distributes in the Sha-3 and Sha-4 Members of the Dongpu Depression. • Disequilibrium compaction and hydrocarbon generation are main overpressure origins. • Two models to identify and quantify different origins' overpressure were came up. • Overpressure origin changes in different tectonic units and evolution stages. [ABSTRACT FROM AUTHOR]

Background: When frozen pathological results of suspicious peritoneal nodules found in gastric cancer (GC) patients are negative or indeterminant, whether to perform gastrectomy will always be a dilemma for surgeons. This study aimed to facilitate intraoperative surgical decision-making based on frozen section (FS) results and clinicopathological characteristics. Methods: From January 2015 to July 2021, 318 GC patients were enrolled retrospectively. The correlations between frozen and paraffin pathology of peritoneal nodules were examined. Then, predictive factors of positive paraffin section (PS) results were identified, and a nomogram was constructed. The survival significance of gastrectomy was also explored. Results: Of 70 FS-negative patients, 59 (84.3%) had concordant negative PS results, while the PS results of 11 (15.7%) were positive. Forty-six (93.9%) and 3 (6.1%) of 49 patients with indeterminant FS results had positive and negative PS results, respectively. The PS results of 95 FS-positive patients were all positive. A nomogram for predicting positive PS results was developed based on Lauren type, nodule distribution, and CA125. Gastrectomy for FS-negative patients improved survival compared to no gastrectomy (HR 0.26, 95% CI 0.11–0.62; P = 0.0012). Survival benefits for gastrectomy vs. no gastrectomy were not demonstrated in patients with indeterminant (HR 0.74, 95% CI 0.27–2.01; P = 0.53) and positive (HR 0.87, 95% CI 0.43–1.74; P = 0.69) FS results. Conclusions: Gastrectomy can be justified for the treatment of operable GC patients with negative frozen pathological results of peritoneal nodules. For patients with positive and indeterminant frozen pathological results, gastrectomy is not recommended unless it is performed as palliative surgery. [ABSTRACT FROM AUTHOR]

Calcium sulfate or plaster of Paris (POP) is considered as a bone cement with a fast degradation rate, which frequently makes it resorb before the bone defect area is completely filled by new bone. The incorporation of tricalcium silicate (C3S) into POP cement has been proven as a feasible approach to reduce the in vitro degradation rate and improve the in vitro bioactivity of the material. However, the in vivo performance of the POP/C3S composite cement is still unclear. Therefore, the aim of the present study is to assess the biodegradability and osteogenesis of POP/C3S composite cement in comparison with those of POP bone cement. To carry out the in vivo evaluation, POP and POP/C3S cements were implanted into a femoral condyle defect model in rabbits (5 mm diameter × 10 mm length) for 4, 8, and 12 weeks duration. The area of the remaining cement and new bone regeneration in bone defect were investigated and quantitatively measured using radiography, micro-computed tomography, and histological staining. For both cements, no sign of inflammation was observed. POP cement was completely degraded at the 8th week of post-implantation. By contrast, only approximately 50% by volume of POP/C3S composite cement degraded at the 12th week, which allowed a long-term framework for new bone formation. The osteogenic ability of POP/C3S composite cement was significantly superior to that of POP as indicated by the higher mineralization rate and maturity of the newly formed bone around the composite cement. In summary, our findings demonstrated that the in vivo degradation behaviors and osteogenic ability of POP cement could be improved by incorporating C3S in vivo, suggesting that POP/C3S composite cement has potential as a biodegradable cement for bone repair. [ABSTRACT FROM AUTHOR]

Background and Aims It has been reported that rs1122608 adjacent to low-density lipoprotein cholesterol receptor (LDLR) locus is associated with the risk of coronary artery disease (CAD) and blood lipid profile in the Caucasian population. Due to the contradictory results in the Asian population, we conducted a meta-analysis to systematically summarize and clarify the association between rs1122608 with CAD risk and lipid profile. Methods A systematic search regarding studies on the association of rs1122608 with CAD risk and lipid profile was conducted in databases including PubMed, Embase, and Cochrane library. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to pool the effect size. Results A total of five case-control studies were included in this study. A statistically significant association was identified between rs1122608-G allele and CAD risk in overall analysis (OR = 2.09, 95% CI 1.48–2.97) and in both Asian (OR = 1.82, 95% CI 1.04–3.18) and Caucasian subgroups (OR = 2.31, 95% CI 1.48–3.60). The rs1122608-G allele was associated with increased triglyceride (TG) level (OR = 1.25, 95% CI 1.03–1.52), but not with total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), or LDL cholesterol level. Moreover, the rs1122608-G allele is associated with increased CAD risk in the Asian male population (OR = 3.37, 95% CI 1.51–9.86) but not in the Asian female population. Conclusions The rs1122608 is associated with the risk of CAD and TG level. The rs1122608-G allele was a significant risk factor of CAD in the Asian male population but not in the Asian female population. [ABSTRACT FROM AUTHOR]

Chlorite is beneficial to the preservation of primary pores, and its formation mechanism in marine sandstone has been widely reported. However, few studies have focused on the genetic mechanism of various types of chlorite in lacustrine deltaic sandstone. Therefore, the occurrence, diagenetic time and origin of chlorite in Xujiahe tight sandstone were investigated using microscopic images and mineralogical chemical analysis, and three stages of chlorite were identified, namely, grain-coating (Ch1), pore-lining (Ch2), and pore-filling (Ch3) chlorite, which belong to the Fe chlorite, Al chlorite and transitional types, respectively. The variations in morphology and chemical composition reflect differences in the sources and formation mechanisms. Chlorite sandstones are mainly distributed in the underwater distributary channel, which has strong hydrodynamic conditions. The formation of Ch1 is controlled by the sedimentary environment and flocculation. Salinity differences resulted in a larger amount of flocculation deposits in the estuaries during the syngenetic period. In the shallow burial stage, the clay coating underwent in situ transformation under thermal impacts and formed the Ch1. Xujiahe sandstones experienced complex diagenetic processes, which include early compaction, three stages of chlorite cementation, two stages of quartz precipitation, dissolution and two stages of carbonate cementation. Organic acid dissolution of volcanic rock fragments, phyllite, and biotite likely supplied sufficient Fe2+ for the growth of Ch2 in a relatively closed diagenetic system. As the pore water became weakly alkaline, diagenetic fluid migration originating from the clay mineral transformation in mudstone mainly provided Fe2+ and Mg2+ for Ch3 growth in sandstones. Chlorite is considered to have "composite" impacts on deep tight sandstones, with grain-coating and pore-lining chlorites protecting the primary pores by restricting the silica supply and occupying potential quartz nucleation sites; however, grain-coating chlorite caused throat obstruction or even closure under strong mechanical compaction, which reduced the permeability of the reservoir. • Three different types of chlorite have been found in the Xujiahe tight sandstones. • It has been clear that the formation time of chlorite and the paragenetic sequence of authigenic minerals. • The origin and formation mechanism of authigenic chlorite in three types have been investigated. • We considerd that authigenic chlorite has a "composite" impact on deep tight sandstone: preserve primary porosity but reduce the permeability. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hollow V2O5 spheres constructed from plate-like particles were synthesized and used as supercapacitor electrodes in a solution of 5M LiNO3. [•] These materials exhibited a tremendous pseudocapacitance effect with a high capacitance of 479Fg−1 at 5mVs−1. [•] The hollow V2O5 spheres was coated with PPy exhibited the capacitances of 559Fg−1 at 3Ag−1 by GCD and 566Fg−1 at 5mVs−1 by CV, respectively. [Copyright &y& Elsevier]

[Display omitted] • A strategy to fabricate conductive SiO 2 @Ga core–shell microparticles is developed. • Maximizing catalytically active surface gallium for electrocatalysis of Li 2 S x. • The addition of microparticles promote the ion transfer kinetics of the electrodes. • A mechanism of conductive electron-given-surface and fast Li+ transport is proposed. • Li-S batteries with high sulfur loading and high specific capacity are achieved. A novel silica@gallium core–shell structure is designed to maximize catalytically active surface gallium for highly efficient electrocatalysis of lithium polysulfides in lithium-sulfur batteries. The fabricated SiO 2 @Ga/S cathode battery exhibits a high reversible capacity of 927.1 mAh g−1 at 0.75C and excellent cycling stability with a capacity retention rate of 85.97% for 600 cycles. When the sulfur mass loading is up to 6.5 mg cm−2, the battery displays a high discharge capacity of ~ 4.145 mAh cm−2 with high Coulombic efficiency of 85.04% after 200 cycles. Finally, a mechanism that the highly conductive electron-given-surface of liquid metal Ga shell on the surface of SiO 2 in the thick electrodes for reversible electrocatalysis of lithium polysulfides in lithium-sulfur batteries is proposed. [ABSTRACT FROM AUTHOR]

• A novel method for defouling fouled outdoor coils in ASHPs has been developed. • The method is based on three directly measurable operating temperatures. • Further field studies to verify the method's applicability were carried out. • The method provided an accurate and convenient way for defouling initiation. Air source heat pumps (ASHPs) have been widely used for space cooling in recent years. When a space cooling ASHP unit is operated in an ambience with poor air quality, fouling of its outdoor coil can be easily built up, leading to a significant drop in the operating efficiency and output cooling capacity of the ASHP unit. Therefore, as a follow-up to a previous related study, a study to develop a novel defouling initiation method for the fouled outdoor coil in a space cooling ASHP unit based on its measurable characteristic ambient and operating temperatures has been carried out and the study results are reported in this paper. Firstly, a characteristic parameter of TTT, which can be evaluated based on ambient air Temperature, outdoor coil metal surface Temperature and outdoor coil outlet air Temperature, is defined. Secondly, the development of the novel defouling initiation method is detailed. Finally, further field comparative studies using the developed novel defouling initiation method have been carried out, and the study results demonstrated that the novel defouling initiation method can provide an accurate and convenient way to initiate defouling of the fouled outdoor coil in an ASHP unit at a reasonable defouling frequency to ensure its best possible operating performances. [ABSTRACT FROM AUTHOR]

Abstract To better understand gas migration and accumulation in tight sandstone reservoirs, we conducted an integrated petrographic and geochemical analysis of hydrocarbon and aqueous fluid inclusions. This analysis was combined with the burial and multistage hydrocarbon charging histories of the reservoir. The variability in the types of hydrocarbon inclusions in the tight sandstone reservoirs can be mapped to identify phase fractionation during burial and migration. The oil-bearing inclusions resulted from the heterogeneous capture of oil generated during the first hydrocarbon charging period, when the sandstones had not yet reached tight reservoir conditions. The gas-bearing inclusions in the tight sandstone reservoirs formed during the phase fractionation of dissolved and free gas due to unstable pressure conditions. The gas-bearing inclusions are characterized by a varying vapor volume fraction (φ vap). A higher proportion of gas-bearing inclusions with φ vap < 25% was observed near the source rock with TOC content >1.2%. In contrast, in structural highs, a higher proportion of gas-water inclusions with φ vap > 25% was observed, demonstrating that phase fractionation occurred during migration. The GOI data suggest that the dissolved gas migration mainly occurred in the reservoir near the source rock with TOC content >1.2%. The subsequent free gas separation in relation to upward migration and strata uplift caused free gas to migrate farther into the tight sandstone reservoir. Additionally, the gases displayed benzene/n-hexane ratio, methane and ethane δ13C values increasing initially, then decreasing along the migration pathway, recording the phase state evolution of the natural gas during the burial history of the reservoirs. Highlights • The paleopressure evolution has been reconstructed. • The geochemical fractionation effects in high and low surplus pressure zone are investigated. • Phase fractionation during the burial history is revealed by fluid inclusion petrography and microthermometry. [ABSTRACT FROM AUTHOR]

Highlights • Impacts of fouling and ambient temperature on ASHP's performances were studied. • Increased fouling level and ambient air temperature led to poorer performances. • An equivalent temperature rise due to fouling was proposed and evaluated. • An improved simulated fouling approach was experimentally validated. Abstract Air source heat pumps (ASHPs) have been widely used for providing buildings with heating in winter and cooling in summer. In certain locations, with an increased level of air pollutions, fouling of the outdoor coil in a space cooling ASHP unit may appear, which affects the operating performances of the ASHP unit. Furthermore, the operating performances of an ASHP unit can also be affected by ambient air temperature (T a). In this paper, a field study on the effects of outdoor coil fouling at different T a on the operating performances of a field space cooling ASHP unit is presented. The study results demonstrated that the operating performances of the field ASHP unit were significantly affected by the changes in both T a and percentage of fouled outdoor coil surface (PFOCS). For example, at T a = 30 °C, the variation in PFOCS from 0 to 100% led to a reduction in COP for the field ASHP unit from 2.7 to 2.0. At a fixed PFOCS of 60%, the changes in T a from 26 to 33 °C resulted in a reduction in COP from 2.6 to 2.1. In order to more conveniently investigate the combined impacts of fouling on the operating performances of an ASHP unit at different T a , an equivalent ambient air temperature rise (ETR) was proposed. Based on the measured and evaluated operating parameters of the field ASHP unit at different T a and PFOCS values, ETR values at 0 - 40%, 40 - 60%, 60 - 100% and 0 - 100% PFOCS ranges were evaluated. These ETR values implied that defouling of a fouled outdoor coil may be initiated when PFOCS was at 40 - 60%. With the ETR values for the full PFOCS range of 0 - 100%, the impact of full fouling on the operating performances of an ASHP unit may be evaluated as if it was operated with a clean outdoor coil but at an equivalent ambient air temperature of T a + ETR. [ABSTRACT FROM AUTHOR]

Abstract The Lower Cretaceous Yingcheng Formation in the Longfengshan sag (Songliao Basin, China) represents a typical tight sandstone reservoir that hosts large accumulations of hydrocarbons. The lacustrine sandstones mainly reflect gravity flow deposits making up various lithofacies displaying varying degrees of heterogeneity. This study reports on the links among gravity flow type, diagenetic overprinting and pore-throat characteristics that control reservoir quality. Core observations, especially grain size variations and related sedimentary structures are used to differentiate types of gravity flows. Microscopic observations, cathodoluminescence, scanning electron microscopy, pressure-controlled mercury injection tests and rate-controlled mercury injection tests are used to determine the mineralogy, sedimentary composition and pore-throat characteristics of the tight sandstones. In the study area, the gravity flows are divided into muddy debris flows, sandy debris flows, high-density turbidity flows, low-density turbidity flows and mud density flows. The petrophysical properties of these different gravity flow sediments reflect a range of permeability and porosity characteristics. Because of their mud-dominated textures and related weak compressive strength, mud density flows and muddy debris flows become ineffective as reservoirs during burial. In contrast, for approximately similar burial depths, turbidites and sandy debris flows show better reservoir quality. However, reservoir units with high porosities still possess considerable heterogeneity; this is especially true of some sandy debris flows that possess large amounts of secondary pores but which are not charged with hydrocarbons. In particular, in some poorly sorted sandy debris flows that are characterized by high contents of fine-grained matrix, some of the pore throats are blocked by matrix material. Moreover, the dissolution of feldspars and volcanic debris led to the formation of authigenic clays and quartz, which preferentially developed in pore throats with small radii. This process significantly reduced permeability. Overall, the permeabilities of the sandy debris flows are generally lower than those of the turbidites. Due to their relatively large-radius pore throats, turbidites can be categorized as potential effective hydrocarbon reservoirs in the study area. This research provides significant insights into the characteristics of pore throats within tight reservoirs consisting of gravity flow sediments in lacustrine basinal settings. Highlights • Gravity flow sediments have been categorized based on sediment support mechanism, flow state and sediment characteristics. • Pore-throat characteristics of different kind of gravity flow sediments are addressed. • Depositional texture and host rock buffered diagenesis are the main factors controlling reservoir quality. • Turbidites have the highest reservoir potential. [ABSTRACT FROM AUTHOR]

Highlights • The TEPS defrosting initiation strategy was applied to mild and humid regions. • Five short-term and two long-term field test cases were conducted. • The TEPS defrosting initiation strategy was compared to the TT initiation strategy. • The use of TEPS strategy led to more accurate and reliable defrosting initiation. • The use of TEPS strategy led to better operating performances of ASHPs. Abstract A defrosting initiation strategy based on tube-encircled photoelectric sensors (TEPS) was previously proven effective for enhancing the frosting-defrosting performances of air source heat pumps (ASHPs) in cold and dry regions. To verify its applicability to, and evaluate the energy-saving potential when using the TEPS-based strategy in mild and humid regions, field tests were conducted in Guiyang City, China, where the outdoor averaged air temperature and relative humidity were 4.5 °C and 80% in winter, respectively. Two ASHPs of the same-make, one with the TEPS-based strategy and the other with the commonly used temperature-time (TT) strategy, were tested. Totally, seven test cases were organised. Cases 1–5 were for short-term tests to verify the technical feasibility of TEPS-based strategy by comparing the defrosting accuracy of the two strategies. Cases 6–7 were for long-term tests to validate the reliability and effectiveness of the TEPS-based strategy by comparing two ASHPs' operating performances. The test results demonstrated that the use of TEPS-based strategy in mild and humid regions can initiate defrosting more accurately, reliably and efficiently, and thus improve the COP and heating capacity by 11.3% and 12.1%, respectively, compared to the use of the TT strategy. Therefore, it was proven that the TEPS-based strategy was more effective for the ASHPs used in mild and humid regions, for a more accurate defrosting initiation and higher energy efficiency. [ABSTRACT FROM AUTHOR]

Aim: To assess efficacy/safety of initial linagliptin/metformin single-pill combination (SPC) therapies versus individual drug components over 24weeks in treatment-naïve Asian patients with type 2 diabetes mellitus and insufficient glycemic control.Methods: Patients (initial glycated hemoglobin [HbA1c] ⩾7.5% to <11.0% [58-97mmol/mol]; main group) were randomized to: linagliptin 5mg once daily (qd); metformin 500mg twice daily (bid); metformin 1000mg bid; linagliptin 2.5mg/metformin 500mg bid; or linagliptin 2.5mg/metformin 1000mg bid. Patients with severe hyperglycemia (HbA1c ⩾11.0% [97mmol/mol]) received linagliptin 2.5mg/metformin 1000mg bid or linagliptin 5mg qd (switched at week 12 from linagliptin to SPC if HbA1c >8.0% [64mmol/mol]). The main group primary endpoint was HbA1c change from baseline to week 24.Results: At week 24, adjusted mean change from baseline in HbA1c (main group, n=733) was: linagliptin 5mg qd, -1.3%; metformin 500mg bid, -1.6%; metformin 1000mg bid, -2.1%; linagliptin 2.5mg/metformin 500mg bid, -2.2%; linagliptin 2.5mg/metformin 1000mg bid, -2.3%. The first test of primary HbA1c analysis (linagliptin 2.5mg/metformin 1000mg bid vs. metformin 1000mg bid) was borderline non-significant; however, SPCs produced significantly greater reductions in HbA1c from baseline versus respective monotherapies in all but one pre-defined sensitivity analysis. In the severe hyperglycemia group (n=143), linagliptin 2.5mg/metformin 1000mg bid produced a superior HbA1c reduction (-4.7%) versus linagliptin 5mg qd (-3.5%) after 12weeks. Hypoglycemic adverse events were low across groups.Conclusions: Initial linagliptin/metformin SPC significantly improved glycemic control in this population. [ABSTRACT FROM AUTHOR]

The practical applications of lithium sulfur batteries have been greatly restricted by the polysulfide shuttle effect and non-conductivity of sulfur. Here, we report a nickel-catalyzed carbonization method to synthesize three-dimensional (3D) nickel@N-doped carbon-nanotube (CNT) foams for lithium-sulfur batteries. The corresponding carbon/sulfur cathode with a high sulfur loading of 3.71 mg cm−2 possesses a high initial capacity of 855.6 mAh g−1 at 135 mA g−1 and good cyclic stability with a low fading rate of 0.153% per cycle for 100 cycles at 270 mA g−1. The growth of carbon thin layers on the nickel nanoparticles results in the encapsulation of the nanoparticles in the CNTs, which makes the carbon forms highly conductive and prevents the metal nanoparticles from being oxidized by polysulfides. The high conductivity is favorable for the electron transfer between polysulfides and carbon electrode. Moreover, the doped nitrogen atoms on the CNTs have strong chemical adsorption ability for polysulfides, accelerating redox reaction of polysulfides on the carbon electrode (i.e., suppressing the shuttle effect). These unique structural characteristics well explain the excellent electrochemical performance of the assembled batteries. It is believed that the fabricated carbon foam is a promising material for high sulfur-loading lithium-sulfur battery. [Display omitted] • Encapsulates carbon-coated Ni metal nanoparticles in N-doped carbon nanotube. • 3D highly conductive network and strongly chemisorptionto polysulfides. • Stable cycle performance of lithium-sulfur battery under high sulfur loading. [ABSTRACT FROM AUTHOR]

To improve the defrosting accuracy of air source heat pumps (ASHPs), this paper proposes a novel defrosting control method by applying tube encircled photoelectric sensors (TEPSs). A field test was conducted for two heating seasons in Beijing, China, to verify the feasibility and practicality of the novel TEPS method. The test results revealed that irrespective of the environmental conditions, the TEPS method can initiate defrosting in similar situations: most of the heat exchanger surface had been covered by frost; the compressor suction temperature decreased by ~9 °C; the compressor discharge temperature increased by ~16 °C; and the heating capacity decreased by ~30%. Furthermore, the TEPS method was verified to make more accurate and more reasonable defrosting decisions than the traditional T-T method under both frosting and non-frosting conditions. The results indicate that the TEPS method is a competitive defrosting control method that can be used for ASHPs. [ABSTRACT FROM AUTHOR]

Sparse representation classification, as one of the state-of-the-art classification methods, has been widely studied and successfully applied in face recognition since it was proposed by Wright et al. In this study, we proposed a method to generate virtual available facial images and modified the well-known linear regression classification (LRC) and collaborative representation based classification (CRC) for face recognition. The new method integrates the original and virtual symmetry facial images to form a training sample set of large size. Experimental results show that the proposed method can achieve better performance than most of the competitive face recognition methods, e.g. LRC, CRC, INNC, SRC, RCR, RRC and the method in Xu et al. (2014). This promising performance is mainly attributed to the fact that the sample combination scheme used in the new method can exploit limited original training samples to produce a large number of available training samples and to convey sufficient variations of the original training samples. [ABSTRACT FROM AUTHOR]

To improve the defrosting accuracy and the energy efficiency of the air-source heat pump (ASHP) under frosting and defrosting conditions, a novel Temperature–Humidity–Time (T–H–T) defrosting control method, based on a frosting map for the ASHP unit, is proposed in this paper. A field test was conducted for two heating seasons, to verify the feasibility and applicability of the T–H–T method. The advantages of the T–H–T method, compared to the conventional Temperature–Time (T–T) defrosting control method, are presented. In total, eight cases are shown in this paper. Cases 1 to 4 were chosen to reveal the T–H–T performance under different frosting conditions. It was found that no matter what kind of frosting conditions, defrosting was always initiated in a similar situation: ∼90% of the outdoor coil surface was covered by frost; the temperature difference between the compressor suction and discharge increased by ∼20%; and the heating capacity decreased by ∼30%. These results indicate that the T–H–T method can make an accurate decision under different frosting conditions. Cases 5a, 5b and Cases 6a, 6b were two groups of cases to compare the advantages of the T–H–T method against the conventional T–T method. Cases 5a and 5b were chosen for the non-frosting condition. It was found that the T–T method initiated the defrosting operation 31 times within 24 h. However, none of the defrosting operations was conducted for the T–H–T method. Cases 6a and 6b were chosen to compare these two methods under consecutive and variable frosting conditions. For the T–T method, 63% of the defrosting processes were found to be executed under conditions where defrosting was not necessary. However, for the T–H–T method, all the defrosting controls were found to be accurate and reasonable. These results indicated that the novel T–H–T method is suitable for the defrosting control of the ASHP, and has a more competitive performance than the conventional T–T method. [ABSTRACT FROM AUTHOR]

The organic-rich shales of the upper Permian Dalong Formation in the middle Yangtze area are considered an important shale gas exploration horizon. However, the origin of siliceous matter and the mechanism of organic matter enrichment are still controversial. Based on geochemical data, we studied the provenance, paleoclimate, paleoenvironment, primary productivity and hydrological conditions of the Dalong Formation in western Hubei Province and discussed the mechanism of organic matter enrichment. The shales of the Dalong Formation can be divided into two units, organic-rich and organic-lean shales, with average TOC contents of 5.81 wt% and 0.45 wt%, respectively. The western Hubei Basin was a strongly restricted basin during deposition, and the provenance of the Dalong Formation had a continental margin sedimentary background, mainly from mixed felsic and basic sources. Terrigenous clastic quartz, biological quartz and hydrothermal quartz are recognized in the shales of the Dalong Formation. Based on U, V, and Mo concentrations and V/(V + Ni) ratios, the organic-rich shales were deposited in anoxic-sulfurized conditions. In contrast, the organic-lean shales were deposited under oxic-suboxic conditions. The Dalong Formation had moderate to high primary productivity and controls on the redox conditions in the basin. The decrease in primary productivity in organic-lean shales may be related to the transition from a warm and humid climate to a hot and dry climate. The sedimentary model shows that the formation of organic-rich siliceous rocks in the Dalong Formation was controlled by primary productivity. The decrease in primary productivity driven by the hot and dry climate in the latest Permian is the main factor controlling the enrichment of organic matter and the formation of bioquartz. • Dalong shale contains terrigenous clastic quartz, biological quartz and hydrothermal quartz. • The anoxic-sulfurized water were widely distributed on the organic-rich shales deposited. • Hot and dry climate caused the reducing primary productivity. • Organic matter enrichment controlled mainly by the primary productivity. [ABSTRACT FROM AUTHOR]

• A new method to fabricate 3D porous sulfur/gallium hybrid materials is developed. • The 3D porous sulfur/gallium hybrid materials increase the electrical and ion conductivity of the cathode. • The 3D porous sulfur/gallium hybrid materials promote the activation of the electrodes. • The surface of liquid metal Ga promote the redox reaction of lithium polysulfides due to its strong electrocatalytic effect. • Li-S batteries with high sulfur loading, long cycling and high specific capacity are achieved. Lithium–sulfur battery has long been considered as the best choice for the next generation secondary battery. However, the intrinsic insulativity of sulfur and the polysulfide shuttle effect have been the key problems that hinder the commercialization of lithium sulfur batteries. Here, using a facile shearing implement assists thermal synthesis process, in which liquid metal gallium and sulfur (mass ratio1:10) are the only reactants, we create a 3D porous sulfur/gallium hybrid materials (S/Ga). Micro/nanometer liquid metal gallium particles embed in the porous sulfur. The S/Ga cathode lithium cell exhibits a high Coulombic efficiencies of 98.7%, and high specific capacities of 1044 mAh g−1 after 100 cycles at 1.0 mA cm−2, and good cyclic stability. During first cycle discharge process of the S/Ga cathode, the sulfur reduces to Li 2 S 8 and dissolves in the electrolyte, then the liquid metal Ga has an intimate electrical contact with conductive carbon substrates. Electrons are easily transferred to high conductive liquid metal Ga. Due to the electron abundance on Ga surface, it shows an electrocatalytic effect for the conversion of soluble lithium polysulfides (Li 2 S 4-8) to Li 2 S 2 /Li 2 S, thus improving S utilization and cyclic stability. Image, graphical abstract [ABSTRACT FROM AUTHOR]