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Gain-enhanced reconfigurable radiation array with mechanically driven system and directive elements

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0716-0

摘要： In the artificial intelligence-driven modern wireless communication system, antennas are required to be reconfigurable in terms of size according to changing application scenarios. However, conventional antennas with constant phase distributions cannot achieve enhanced gains in different reconfigurable sizes. In this paper, we propose a mechanically reconfigurable radiation array (RRA) based on miniaturized elements and a mechanically reconfigurable system to obtain gain-enhanced antennas in compact and deployed states. A five-element RRA with a phase-reconfigurable center element is designed and analyzed theoretically. The experimental sample has been fabricated, driven by a deployable frame with only one degree of freedom to realize the size and phase distribution reconfiguration simultaneously to validate the enhanced gains of RRA. The proposed RRA can be tessellated into larger arrays to achieve higher gains in other frequency regimes, such as terahertz or photonics applications with nanometer fabrication technology.

关键词： mechanism reconfigurable radiation array (RRA) compact state deployed state enhanced gain

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A reversibility-gain model for integer Karhunen-Loève transform design in video coding

Xing-guo ZHU,Lu YU

《信息与电子工程前沿（英文）》 2015年第16卷第10期页码 883-891 doi: 10.1631/FITEE.1500071

摘要： Karhunen-Loève transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical problem. In this paper, a joint reversibility-gain (R-G) model is proposed for integer-KLT design in video coding. Specifically, the ‘reversibility’ is modeled according to distortion analysis in using forward and inverse integer transform without quantization. It not only measures how invertible a transform is, but also bounds the distortion introduced by the non-orthonormal integer transform process. The ‘gain’ means transform coding gain (TCG), which is a widely used criterion for transform design in video coding. Since KLT maximizes the TCG under some assumptions, here we define the TCG loss ratio (LR) to measure how much coding gain an integer-KLT loses when compared with the original KLT. Thus, the R-G model can be explained as follows: subject to a certain TCG LR, an integer-KLT with the best reversibility is the optimal integer transform for a given non-integer-KLT. Experimental results show that the R-G model can guide the design of integer-KLTs with good performance.

关键词： Integer transform Karhunen-Loè ve transform (KLT) Integer-KLT Transform coding Video coding

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FUNCTIONAL GAIN OF FRUIT NETTED-CRACKING IN AN INTROGRESSION LINE OF TOMATO WITH HIGHER EXPRESSION OF

《农业科学与工程前沿（英文）》 2021年第8卷第2期

摘要：

Fruit cracking is a major disorder that affects the integrity of fruit and reduces the commercial value of tomato and other fleshy fruit. Here, we have found a novel fruit ‘netted-cracking’ (FNC) phenotype in tomato introgression line IL4-4 which is present in neither the donor parent (LA0716) nor the receptor parent (M82). An F₂ population was generated by crossing IL4-4 with M82 to genetically characterize the FNC gene and this showed that a single dominant gene determined fruit netted-cracking. Further map-based cloning narrowed down the FNC locus to a 230 kb region on chromosome 4. Sequencing and annotation analysis show that FNC(Solyc04 g082540) was the most likely candidate gene. Functional characterization of FNC by overexpressing FNC^AC and FNC^IL4-4resulted in the fruit netted-cracking phenotype, suggesting that the FNC transcript level results in the functional gain of fruit netted-cracking. These findings were further confirmed by FNC ortholog in netted-cracking pepper and melon, indicating a common regulatory mechanism in different plant species. Furthermore, cytoplasm and nucleus-localized FNC indicates increased expression of genes involved in suberin, lignin, lipid transport and cell wall metabolism. These findings provide novel genetic insights into fruit netted-cracking and offer a way to promote molecular improvement toward cracking resistant cultivars.

关键词： fine mapping / fruit netted-cracking / introgression line / transcript level

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手机直连卫星，未来可期

Mitch Leslie

《工程（英文）》 2023年第28卷第9期页码 4-6 doi: 10.1016/j.eng.2023.07.003

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Nanoparticle-enhanced coolants in machining: mechanism, application, and prospects

《机械工程前沿（英文）》 2023年第18卷第4期 doi: 10.1007/s11465-023-0769-8

摘要： Nanoparticle-enhanced coolants (NPECs) are increasingly used in minimum quantity lubrication (MQL) machining as a green lubricant to replace conventional cutting fluids to meet the urgent need for carbon emissions and achieve sustainable manufacturing. However, the thermophysical properties of NPEC during processing remain unclear, making it difficult to provide precise guidance and selection principles for industrial applications. Therefore, this paper reviews the action mechanism, processing properties, and future development directions of NPEC. First, the laws of influence of nano-enhanced phases and base fluids on the processing performance are revealed, and the dispersion stabilization mechanism of NPEC in the preparation process is elaborated. Then, the unique molecular structure and physical properties of NPECs are combined to elucidate their unique mechanisms of heat transfer, penetration, and anti-friction effects. Furthermore, the effect of NPECs is investigated on the basis of their excellent lubricating and cooling properties by comprehensively and quantitatively evaluating the material removal characteristics during machining in turning, milling, and grinding applications. Results showed that turning of Ti‒6Al‒4V with multi-walled carbon nanotube NPECs with a volume fraction of 0.2% resulted in a 34% reduction in tool wear, an average decrease in cutting force of 28%, and a 7% decrease in surface roughness Ra, compared with the conventional flood process. Finally, research gaps and future directions for further applications of NPECs in the industry are presented.

关键词： nanoparticle-enhanced coolant minimum quantity lubrication biolubricant thermophysical properties turning milling grinding

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FUNCTIONAL GAIN OF FRUIT NETTED-CRACKING IN AN INTROGRESSION LINE OF TOMATO WITH HIGHER EXPRESSION OF

Chunli ZHANG, Taotao WANG, Jing LI, Danqiu ZHANG, Qingmin XIE, Shoaib MUNIR, Jie YE, Hanxia LI, Yongen LU, Changxian YANG, Bo OUYANG, Yuyang ZHANG, Junhong ZHANG, Zhibiao YE

《农业科学与工程前沿（英文）》页码 280-291 doi: 10.15302/J-FASE-2020374

摘要： Fruit cracking is a major disorder that affects the integrity of fruit and reduces the commercial value of tomato and other fleshy fruit. Here, we have found a novel fruit ‘netted-cracking’ (FNC) phenotype in tomato introgression line IL4-4 which is present in neither the donor parent (LA0716) nor the receptor parent (M82). An F population was generated by crossing IL4-4 with M82 to genetically characterize the gene and this showed that a single dominant gene determined fruit netted-cracking. Further map-based cloning narrowed down the locus to a 230 kb region on chromosome 4. Sequencing and annotation analysis show that (Solyc04 g082540) was the most likely candidate gene. Functional characterization of by overexpressing and resulted in the fruit netted-cracking phenotype, suggesting that the transcript level results in the functional gain of fruit netted-cracking. These findings were further confirmed by ortholog in netted-cracking pepper and melon, indicating a common regulatory mechanism in different plant species. Furthermore, cytoplasm and nucleus-localized indicates increased expression of genes involved in suberin, lignin, lipid transport and cell wall metabolism. These findings provide novel genetic insights into fruit netted-cracking and offer a way to promote molecular improvement toward cracking resistant cultivars.

关键词： fine mapping fruit netted-cracking introgression line transcript level

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A review on the application of nanofluids in enhanced oil recovery

《化学科学与工程前沿（英文）》 2022年第16卷第8期页码 1165-1197 doi: 10.1007/s11705-021-2120-4

摘要： Enhanced oil recovery (EOR) has been widely used to recover residual oil after the primary or secondary oil recovery processes. Compared to conventional methods, chemical EOR has demonstrated high oil recovery and low operational costs. Nanofluids have received extensive attention owing to their advantages of low cost, high oil recovery, and wide applicability. In recent years, nanofluids have been widely used in EOR processes. Moreover, several studies have focused on the role of nanofluids in the nanofluid EOR (N-EOR) process. However, the mechanisms related to N-EOR are unclear, and several of the mechanisms established are chaotic and contradictory. This review was conducted by considering heavy oil molecules/particle/surface micromechanics; nanofluid-assisted EOR methods; multiscale, multiphase pore/core displacement experiments; and multiphase flow fluid-solid coupling simulations. Nanofluids can alter the wettability of minerals (particle/surface micromechanics), oil/water interfacial tension (heavy oil molecules/water micromechanics), and structural disjoining pressure (heavy oil molecules/particle/surface micromechanics). They can also cause viscosity reduction (micromechanics of heavy oil molecules). Nanofoam technology, nanoemulsion technology, and injected fluids were used during the EOR process. The mechanism of N-EOR is based on the nanoparticle adsorption effect. Nanoparticles can be adsorbed on mineral surfaces and alter the wettability of minerals from oil-wet to water-wet conditions. Nanoparticles can also be adsorbed on the oil/water surface, which alters the oil/water interfacial tension, resulting in the formation of emulsions. Asphaltenes are also adsorbed on the surface of nanoparticles, which reduces the asphaltene content in heavy oil, resulting in a decrease in the viscosity of oil, which helps in oil recovery. In previous studies, most researchers only focused on the results, and the nanoparticle adsorption properties have been ignored. This review presents the relationship between the adsorption properties of nanoparticles and the N-EOR mechanisms. The nanofluid behaviour during a multiphase core displacement process is also discussed, and the corresponding simulation is analysed. Finally, potential mechanisms and future directions of N-EOR are proposed. The findings of this study can further the understanding of N-EOR mechanisms from the perspective of heavy oil molecules/particle/surface micromechanics, as well as clarify the role of nanofluids in multiphase core displacement experiments and simulations. This review also presents limitations and bottlenecks, guiding researchers to develop methods to synthesise novel nanoparticles and conduct further research.

关键词： nanofluid EOR mechanism nanoparticle adsorption interface property internal property

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Generation of enhanced stability of SnO/In(OH)/InP for photocatalytic water splitting by SnO protection

《能源前沿（英文）》 2021年第15卷第3期页码 710-720 doi: 10.1007/s11708-021-0764-x

摘要： InP shows a very high efficiency for solar light to electricity conversion in solar cell and may present an expectation property in photocatalytic hydrogen evolution. However, it suffers serious corrosion in water dispersion. In this paper, it is demonstrated that the stability and activity of the InP-based catalyst are effectively enhanced by applying an anti-corrosion SnO layer and In(OH)₃ transition layer, which reduces the crystal mismatch between SnO and InP and increases charge transfer. The obtained Pt/SnO/In(OH)₃/InP exhibits a hydrogen production rate of 144.42 µmol/g in 3 h under visible light illumination in multi-cycle tests without remarkable decay, 123 times higher than that of naked In(OH)₃/InP without any electron donor under visible irradiation.

关键词： SnO/In(OH)₃/InP photocatalyst enhanced activity and stability for water splitting corrosion inhibition enhancing charge transfer and decreasing crystal mismatch

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CO, N, and CO/N mixed gas injection for enhanced shale gas recovery and CO geological storage

《能源前沿（英文）》 2023年第17卷第3期页码 428-445 doi: 10.1007/s11708-023-0865-9

摘要： In this work, using fractured shale cores, isothermal adsorption experiments and core flooding tests were conducted to investigate the performance of injecting different gases to enhance shale gas recovery and CO₂ geological storage efficiency under real reservoir conditions. The adsorption process of shale to different gases was in agreement with the extended-Langmuir model, and the adsorption capacity of CO₂ was the largest, followed by CH_4, and that of N₂ was the smallest of the three pure gases. In addition, when the CO₂ concentration in the mixed gas exceeded 50%, the adsorption capacity of the mixed gas was greater than that of CH₄, and had a strong competitive adsorption effect. For the core flooding tests, pure gas injection showed that the breakthrough time of CO₂ was longer than that of N₂, and the CH₄ recovery factor at the breakthrough time (

R C H 4

) was also higher than that of N₂. The

R C H 4

of CO₂ gas injection was approximately 44.09%, while the

R C H 4

of N₂ was only 31.63%. For CO₂/N₂ mixed gas injection, with the increase of CO₂ concentration, the

R C H 4

increased, and the

R C H 4

for mixed gas CO₂/N₂ = 8:2 was close to that of pure CO₂, about 40.24%. Moreover, the breakthrough time of N₂ in mixed gas was not much different from that when pure N₂ was injected, while the breakthrough time of CO₂ was prolonged, which indicated that with the increase of N₂ concentration in the mixed gas, the breakthrough time of CO₂ could be extended. Furthermore, an abnormal surge of N₂ concentration in the produced gas was observed after N₂ breakthrough. In regards to CO₂ storage efficiency (

S s t o r a g e - C O 2

), as the CO₂ concentration increased,

S s t o r a g e - C O 2

also increased. The

S s t o r a g e - C O 2

of the pure CO₂ gas injection was about 35.96%, while for mixed gas CO₂/N₂ = 8:2,

S s t o r a g e - C O 2

was about 32.28%.

关键词： shale gas gas injection competitive adsorption enhanced shale gas recovery CO₂ geological storage

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A MYB-INDUCED MECHANISM FOR ENHANCED ASCORBATE IN RED-FLESHED APPLES

Richard V. ESPLEY, Kuilin WANG

《农业科学与工程前沿（英文）》页码 356-357 doi: 10.15302/J-FASE-2021381

摘要： The results presented in “The anthocyanin biosynthetic regulator MdMYB1 positively regulates ascorbic acid biosynthesis in apple” (An et al., this issue) provide evidence for a new mechanism for the elevation of ascorbate concentration in apple. Using a red-fleshed apple breeding population, the authors show how the anthocyanin-regulating MYB transcription factor, MdMYB1, also increases ascorbate concentrations by directly activating transcription of the dehydroascorbate reductase gene . This gene recycles oxidized ascorbate back to ascorbate, leading to elevated concentrations of vitamin C. These red-fleshed apples have enhanced concentrations of both anthocyanins and ascorbate, both of which are appealing traits for the development of healthier apples.

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Activated carbon induced oxygen vacancies-engineered nickel ferrite with enhanced conductivity for supercapacitor

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 2088-2100 doi: 10.1007/s11705-023-2352-6

摘要： Activated carbon induced oxygen vacancies-engineered nickel ferrite with enhanced conductivity for supercapacitor application

关键词： nickel ferrite conductivity carbon oxygen vacancies

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Laser enhanced gettering of silicon substrates

Daniel CHEN,Matthew EDWARDS,Stuart WENHAM,Malcolm ABBOTT,Brett HALLAM

《能源前沿（英文）》 2017年第11卷第1期页码 23-31 doi: 10.1007/s11708-016-0441-7

摘要： One challenge to the use of lightly-doped, high efficiency emitters on multicrystalline silicon wafers is the poor gettering efficiency of the diffusion processes used to fabricate them. With the photovoltaic industry highly reliant on heavily doped phosphorus diffusions as a source of gettering, the transition to selective emitter structures would require new alternative methods of impurity extraction. In this paper, a novel laser based method for gettering is investigated for its impact on commercially available silicon wafers used in the manufacturing of solar cells. Direct comparisons between laser enhanced gettering (LasEG) and lightly-doped emitter diffusion gettering demonstrate a 45% absolute improvement in bulk minority carrier lifetime when using the laser process. Although grain boundaries can be effective gettering sites in multicrystalline wafers, laser processing can substantially improve the performance of both grain boundary sites and intra-grain regions. This improvement is correlated with a factor of 6 further decrease in interstitial iron concentrations. The removal of such impurities from multicrystalline wafers using the laser process can result in intra-grain enhancements in implied open-circuit voltage of up to 40 mV. In instances where specific dopant profiles are required for a diffusion on one surface of a solar cell, and the diffusion process does not enable effective gettering, LasEG may enable improved gettering during the diffusion process.

关键词： gettering multicystaline silicon impurities laser doping

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Fluoride ions adsorption from water by CaCO enhanced Mn–Fe mixed metal oxides

《化学科学与工程前沿（英文）》 2023年第17卷第2期页码 236-248 doi: 10.1007/s11705-022-2193-8

摘要： Novel CaCO₃-enhanced Mn–Fe mixed metal oxides (CMFC) were successfully prepared for the first time by a simple-green hydrothermal strategy without any surfactant or template combined with calcination process. These oxides were then employed as an adsorbent for adsorptive removal of excess fluoride ions. The adsorbent was characterized by SEM, XPS, XRD, FTIR, and BET analysis techniques. The adsorption property of CMFC toward fluoride ion was analyzed by batch experiments. In fact, CMFC exhibited adsorption capacity of 227.3 mg∙g^‒1 toward fluoride ion. Results showed that ion exchange, electrostatic attraction and chemical adsorption were the main mechanism for the adhesion of large amount of fluoride ion on the CMFC surface, and the high adsorption capacity responded to the low pH of the adsorption system. When the fluoride ion concentration was increased from 20 to 200 mg∙L^‒1, Langmuir model was more in line with experimental results. The change of fluoride ion adsorption with respect to time was accurately described by pseudo-second-order kinetics. After five cycles of use, the adsorbent still maintains a performance of 70.6% of efficiency, compared to the fresh adsorbent. Therefore, this material may act as a potential candidate for adsorbent with broad range of application prospects.

关键词： mesoporous materials metal oxides fluoride ion adsorption mechanism

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Sulfur and carbon co-doped g-CN microtubes with enhanced photocatalytic H production activity

《能源前沿（英文）》 doi: 10.1007/s11708-023-0899-z

摘要： Metal-free graphitic carbon nitride (g-C₃N₄) has captured significant attention as a low-cost and efficient hydrogen production photocatalyst through. Effectively regulating the microstructure and accelerating the separation of photogenerated carriers remain crucial strategies for promoting the photocatalytic performance of this material. Herein, a novel sulfur–carbon co-doped g-C₃N₄ (SCCN) hierarchical microtubules filled with abundant nanosheets inside by thermal polymerization is reported. Numerous nanosheets create abundant pores and cavities inside the SCCN microtubes, thereby increasing the specific surface area of g-C₃N₄ and providing sufficient reactant attachment sites. Besides, the hierarchical structure of SCCN microtubules strengthens the reflection and scattering of light, and the utilization of visible light is favorably affected. More importantly, co-doping S and C has greatly improved the photocatalytic performance of graphitic carbon nitride, optimized the band gap structure and enhanced the photogenerated carrier splitting. Consequently, the SCCN exhibits a remarkable photocatalytic H₂ evolution rate of 4868 μmol/(g·h). This work demonstrates the potential of multi-nonmetal doped g-C₃N₄ as the ideal photocatalyst for H₂ evolution.

关键词： carbon nitride photocatalysis hydrogen production

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Enhanced production of

Shen Huang,Xudong Feng,Chun Li

《化学科学与工程前沿（英文）》 2015年第9卷第4期页码 501-510 doi: 10.1007/s11705-015-1544-0

摘要： -Glucuronidase from Li-3 (PGUS) can efficiently hydrolyze glycyrrhizin into the more valuable glycyrrhetic acid monoglucuronide. However, a low productivity of PGUS and the lack of an effective separation strategy have significantly limited its industrial applications. Therefore, the production of PGUS has been improved by optimizing both the fermentation and purification strategies. A two-stage fermentation strategy was developed where PGUS was first grown with glucose and then PGUS was produced in the presence of glycyrrhizin as an inducer. By using this strategy, the biomass was increased 1.5 times and the PGUS activity increased 5.4 times compared to that when glycyrrhizin was used as the sole carbon source. The amount of PGUS produced was increased another 16.6% when the fermentation was expanded to a 15-L fermenter. An effective protocol was also established to purify the PGUS using a sequential combination of hydrophobic, strong anion-exchange and gel filtration chromatography. This protocol had a recovery yield of 6% and gave PGUS that was 39 times purer than the crude PGUS. The purified PGUS had a specific activity of 350 U·mg .

关键词： β-glucuronidase glycyrrhetic acid monoglucuronide cell disruption purification chromatography

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标题作者时间类型操作

Gain-enhanced reconfigurable radiation array with mechanically driven system and directive elements

期刊论文

A reversibility-gain model for integer Karhunen-Loève transform design in video coding

Xing-guo ZHU,Lu YU

期刊论文

FUNCTIONAL GAIN OF FRUIT NETTED-CRACKING IN AN INTROGRESSION LINE OF TOMATO WITH HIGHER EXPRESSION OF

期刊论文

手机直连卫星，未来可期

Mitch Leslie

期刊论文

Nanoparticle-enhanced coolants in machining: mechanism, application, and prospects

期刊论文

FUNCTIONAL GAIN OF FRUIT NETTED-CRACKING IN AN INTROGRESSION LINE OF TOMATO WITH HIGHER EXPRESSION OF

Chunli ZHANG, Taotao WANG, Jing LI, Danqiu ZHANG, Qingmin XIE, Shoaib MUNIR, Jie YE, Hanxia LI, Yongen LU, Changxian YANG, Bo OUYANG, Yuyang ZHANG, Junhong ZHANG, Zhibiao YE

期刊论文

A review on the application of nanofluids in enhanced oil recovery

期刊论文

Generation of enhanced stability of SnO/In(OH)/InP for photocatalytic water splitting by SnO protection

期刊论文

CO, N, and CO/N mixed gas injection for enhanced shale gas recovery and CO geological storage

期刊论文

A MYB-INDUCED MECHANISM FOR ENHANCED ASCORBATE IN RED-FLESHED APPLES

Richard V. ESPLEY, Kuilin WANG

期刊论文

Activated carbon induced oxygen vacancies-engineered nickel ferrite with enhanced conductivity for supercapacitor

期刊论文