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The uncertainties of distribution generations (DGs) and loads lead to severe voltage fluctuations in active distribution networks (ADNs). Meanwhile, energy storage systems (ESSs) and static var compensators (SVCs) can mitigate the uncertainties of power injections by regulating the active and reactive power. Considering the variations of multiple uncertain factors, this paper proposes a complex affine arithmetic (CAA) based uncertain sensitivity analysis method of voltage fluctuations in ADNs. First, affine models of active and reactive power injections are established. The correlations of noisy symbols are used to reflect the mitigation effects of ESSs and SVCs on the uncertainties introduced by DGs and loads. Next, sensitivity indicators of voltage fluctuations are defined based on the transitivity of noisy symbols. Then, a calculation method for sensitivity indicators based on the micro-increments of coefficients is proposed. Combined with the obtained indicators, a fast sensitivity method for calculating interval values of voltages is further proposed. The modified IEEE 33-bus system is tested to validate the accuracy and efficiency of the proposed method by comparison with the continuous utilization of power flow method. Moreover, the 292-bus system is tested to validate its applicability in a large distribution system. Facts have proved that this method improves the efficiency and reliability of calculations, and in different scenarios, it can achieve fast calculation of nodes and online analysis of the voltage fluctuation range in uncertain environments, provides an effective tool for voltage quality management in active distribution networks.

Amorphous materials inherit short- and medium-range order from the corresponding crystal and thus preserve some of its properties while still exhibiting novel properties.sup.1,2. Due to its important applications in technology, amorphous carbon with sp.sup.2 or mixed sp.sup.2-sp.sup.3 hybridization has been explored and prepared.sup.3,4, but synthesis of bulk amorphous carbon with sp.sup.3 concentration close to 100% remains a challenge. Such materials inherit the short-/medium-range order of diamond and should also inherit its superior properties.sup.5. Here, we successfully synthesized millimetre-sized samples--with volumes 10.sup.3-10.sup.4 times as large as produced in earlier studies--of transparent, nearly pure sp.sup.3 amorphous carbon by heating fullerenes at pressures close to the cage collapse boundary. The material synthesized consists of many randomly oriented clusters with diamond-like short-/medium-range order and possesses the highest hardness (101.9 [plus or minus] 2.3 GPa), elastic modulus (1,182 [plus or minus] 40 GPa) and thermal conductivity (26.0 [plus or minus] 1.3 W m.sup.-1 K.sup.-1) observed in any known amorphous material. It also exhibits optical bandgaps tunable from 1.85 eV to 2.79 eV. These discoveries contribute to our knowledge about advanced amorphous materials and the synthesis of bulk amorphous materials by high-pressure and high-temperature techniques and may enable new applications for amorphous solids. Preparing amorphous phases of carbon with mostly sp.sup.3 bonding in bulk is challenging, but macroscopic samples that are nearly pure sp.sup.3 are synthesized here by heating fullerenes at high pressure., Author(s): Yuchen Shang [sup.1] , Zhaodong Liu [sup.1] [sup.2] , Jiajun Dong [sup.1] , Mingguang Yao [sup.1] , Zhenxing Yang [sup.1] , Quanjun Li [sup.1] , Chunguang Zhai [sup.1] , [...]

It is urgent to develop a polyamide (PA) thin-film composite (TFC) membrane with a new method in this study by designing and constructing a new nanomaterial support layer instead of the conventional support layer. Polydopamine-wrapped single-walled carbon nanotubes (PDA@MWCNTs) as the place of the polymerization reaction can optimize the PA film structure and performance. The resulting composite membrane presents a higher water flux of 15.8 L·m−2·h−1·bar−1 and a rejection rate of 97% to Na2SO4, simultaneously maintaining this high separation performance in 300 min. It is a new ideal to construct novel support layer by using inorganic nanoparticles and organic polymer nanofiber membranes. [ABSTRACT FROM AUTHOR]

As one of the most likely alternatives to traditional vapor compression refrigeration technology, solid refrigeration technology based on the barocaloric effect (BCE) has attracted extensive attention in recent years. Spin-crossover (SCO) compounds are considered suitable for working at low driving pressures due to high-pressure sensitivity and small hysteresis width. However, the entropy change (ΔSSCO) of the SCO compound is smaller than that of other excellent barocaloric materials (plastic crystals and two-dimensional perovskites). Here, we report the BCE of the SCO compound {Fe(pz)2(BH3CN)2} (pz = pyrazine) with a smaller molar mass and a third source of entropy change besides electron and vibrational entropy changes. Compound {Fe(pz)2(BH3CN)2} exhibits high pressure sensitivity ( d T 1 / 2 d P = 20.2 K kbar−1) as well as entropy change (Δ S SCO = 202 J kg−1 K−1). The maximum values of reversible isothermal entropy change (ΔSit,rev,max) and adiabatic temperature change (ΔTad,rev,max) at 1 kbar are only 103 J kg−1 K−1 and ∼0 K, respectively, due to the hysteresis behavior. However, at sufficiently high driving pressures, ΔSit,rev,max exceeds 200 J kg−1 K−1, and ΔTad,rev,max can reach ∼47 K, which exceeds all SCO compounds reported in BCE studies and is comparable to some plastic-crystalline and two-dimensional perovskite barocaloric materials. The excellent BCE of the SCO compound {Fe(pz)2(BH3CN)2} is mainly due to its small molar mass, which makes the unit mass compound exhibit higher ΔSSCO, while the introduction of the third source of entropy change—the reorientation entropy change (ΔSreo), only plays a small role. This is expected to promote the practical application of SCO compounds as barocaloric refrigerants. [ABSTRACT FROM AUTHOR]

Two-dimensional layered metal dichalcogenides have given rise to considerable interest in electronics and optoelectronics fields because of their excellent physical and chemical properties and promising applications. Tin disulfide (SnS2) is an important member of them due to its environment-friendly and resource-rich characteristics. Here, a series of in situ electrical transport experiments and photocurrent measurements under high pressure have been performed to investigate the electrical and opto-electrical properties of 4H-SnS2. With increasing pressure, the electrical resistivity of 4H-SnS2 decrease significantly, leading to a transition from semiconducting to metallic state above 58.6 GPa. The increase in pressure results in a substantial enhancement in photoelectric activity, indicating the extensive potential of utilizing pressure as a trigger for in situ optoelectronic applications. Combined with our previous results of x-ray diffraction and optical absorption at high pressure, pressure-induced structural distortion, bandgap narrowing, metallization, and enhancement of photoelectric activity of 4H-SnS2 are tunable and reversible, which are of great significance for both fundamental research and device design. [ABSTRACT FROM AUTHOR]

Wetlands are widely distributed all over the world, and have many wildlife resources, which are the main pieces of the puzzle for natural resource conservation and sustainable development on earth and have important irreplaceability. In this paper, through questionnaire survey, field research, literature review, etc., importance weight analysis was conducted by using principal component analysis, and field survey and questionnaire were carried out to collect data on ecological environment function, environmental protection function, landscape beautification function, disaster prevention and mitigation function of urban wetlands. The problems in wetland parks of Nanjing were discussed, such as lack of awareness of landscape planning, deficient late management of wetland parks, weak ability of sustainable development, and unreasonable landscape layout and function. Finally, corresponding solutions were proposed, such as adhering to the planning and design of urban wetland parks with green as the base and health as the basis, persisting in the construction of a wetland system with high biodiversity and near-natural characteristics, adhering to the principle of sustainable development, adopting the construction idea of symbiosis and circulation of urban wetland parks, strengthening education and publicity work, and paying attention to the organic combination of system protection and coordinated construction. The research can build a new development direction for the model of urban wetland parks and green healthy cities, and provide theoretical support for urban sustainable construction. [ABSTRACT FROM AUTHOR]

City park undertakes the function of urban core green island. Hefei Xiaoyaojin Park provides a leisure and entertainment place for Hefei citizens. Although it has been continuously transformed and upgraded, there are still many places to be improved. Through behavior observation and questionnaire, the usage and satisfaction evaluation of tourists in Xiaoyaojin Park were obtained, and the transformation design of Xiaoyaojin Park was analyzed from the perspective of behavior psychology by analyzing the behavior of tourists in different zones of Xiaoyaojin. Based on the premise of exploring the behavior of tourists in different spaces, a city park environment that meets the needs of tourists can be created by promoting the cultural context of the Three Kingdoms, improving the plant landscape and infrastructure of the site, optimizing the spatial function, and exploring the park design and transformation strategy that is more in line with the needs of people, in order to provide new ideas for the future landscape transformation of Xiaoyaojin park, and offer reference suggestions for the future transformation design of old city parks. [ABSTRACT FROM AUTHOR]

With the proposal of the concept that lucid waters and lush mountains are invaluable assets, ecological issues have become increasingly important issues of concern to people. The process of urbanization is accelerating, and the importance of urban waterfront space in improving the environmental quality of the city and people's quality of life, enhancing the vitality of the city, the overall appearance of the city, and the competitiveness of the city, is receiving increasing attention. And how to properly handle the construction and development of urban waterfront space has become increasingly prominent in urban planning. Under the the concept of "ecological conservation", it is thought that the construction of urban waterfront space should follow the principle of harmony between nature and man, and strengthen the multifaceted connection of the city. Through field research on Swan Lake, a comprehensive evaluation of the problems in the plank road and land ecology is conducted. It is proposed to improve the current situation of Swan Lake by grasping the two keywords of "waterfront" and "city", and starting from the improvement of water body and the enhancement of urban cultural construction in the lake area. [ABSTRACT FROM AUTHOR]

In the campus greening design, the shrub height is generally consistent with people's horizontal line of sight, which plays a significant role in people's visual focus. From the perspective of ornamental characteristics of plants, the application of shrub landscape is explored in a campus environment. Based on the analysis of the selection, arrangement and maintenance of shrub plants in campus gardens, the application of shrub landscape on campus was evaluated comprehensively from the theoretical analysis of plant ornamental characteristics and campus shrub landscape. Based on the research background of the problems existing in the application of shrub landscape on campus, this paper first collected and sorted out the relevant theories extensively, and then conducted in-depth research on the relevant theories by using analysis methods such as literature data, field investigation and questionnaire survey. The results will provide a theoretical guidance and practical advocacy for campus garden planning and design, and help to create a livable and comfortable campus environment. It is hoped that the results will have some references for future campus shrub landscape and play a certain promoting role. [ABSTRACT FROM AUTHOR]

As a member of the emerging MXenes family, Nb2CS2 offers distinctive superconductivity, excellent electrical properties, and outstanding chemical stability, making it potentially useful for energy storage, medical imaging, and quantum computing. Herein, we systematically investigate how ultrahigh pressure affects the electrical properties of Nb2CS2. The results indicate that Nb2CS2 retains robust superconductivity with T c > 8 K up to the maximum applied pressure of 146.8 GPa. Moreover, the upper critical magnetic field H c 2 (0) of Nb2CS2 increases with pressure, and the Pauli limit is violated at pressures greater than 120 GPa. Meanwhile, H c 2 (0) increases to 19.3 T at 146.8 GPa, which is 4.8 times greater than at the initial pressure. Further analysis suggests that the significant enhancement of H c 2 (0) below 30 GPa comes from the sharp pressure-induced rise of carrier concentration as the interlayer distance decreases, and the significant increase in H c 2 (0) above 86 GPa may come from enhanced spin–orbit coupling or the possible unconventional superconducting pairing mechanisms. These results provide insights into the superconducting properties of MXene materials and offer guidelines for further research on electronic transport in Mxenes under ultrahigh pressure. [ABSTRACT FROM AUTHOR]

Organic–inorganic halide perovskites (HOIPs) are promising light-electric conversion materials for optoelectronic devices. Improving the light responsiveness properties of HOIPs is of great significance for the development of the optoelectronics industry. In this study, we have investigated the effect of pressure on the optoelectronics properties of the archetypical representative HOIPs methylammonium lead iodide nanoplates. An enhancement of the photocurrent accompanied by 4 times-prolonged carrier lifetime, enhanced photoluminescence (PL) intensity, and narrowed bandgap were observed via applying pressure to about 0.36 GPa, while these physical properties got worse with further compression. Strikingly, when released to ambient conditions, the photocurrent is further increased to 4.5 times and the carrier lifetime is prolonged to 1.5 times of the corresponding values for an initial sample, while the bandgap slightly blueshifted and the PL intensity slightly reduced. These results suggest that the increased photocurrent may be related to the increased carrier lifetime of the quenched sample, which gives more time for the separation of photoelectrons from vacancies before recombination. This study demonstrated that pressure engineering can be a real possibility for improving the light responsiveness of the HOIPs material in practical applications. [ABSTRACT FROM AUTHOR]

Effective modification of the structure and properties of halide perovskites via the pressure engineering strategy has attracted enormous interest in the past decade. However, sufficient effort and insights regarding the potential properties and applications of the high‐pressure amorphous phase are still lacking. Here, the superior and tunable photoelectric properties that occur in the pressure‐induced amorphization process of the halide perovskite Cs3Bi2I9 are demonstrated. With increasing pressure, the photocurrent with xenon lamp illumination exhibits a rapid increase and achieves an almost five orders of magnitude increment compared to its initial value. Impressively, a broadband photoresponse from 520 to 1650 nm with an optimal responsivity of 6.81 mA W−1 and fast response times of 95/96 ms at 1650 nm is achieved upon successive compression. The high‐gain, fast, broadband, and dramatically enhanced photoresponse properties of Cs3Bi2I9 are the result of comprehensive photoconductive and photothermoelectric mechanisms, which are associated with enhanced orbital coupling caused by an increase in BiI interactions in the [BiI6]3− cluster, even in the amorphous state. These findings provide new insights for further exploring the potential properties and applications of amorphous perovskites. [ABSTRACT FROM AUTHOR]

Here, we report significant pressure-modulate optoelectronic properties of NiPS3. Upon compression, NiPS3 exhibited a photocurrent increase of five orders of magnitude over the initial value. Interestingly, when NiPS3 was finally decompressed to ambient conditions, the photocurrent could maintain a two-order-of-magnitude enhancement. In addition, the spectral response range was extended to the near-infrared spectral range (up to 1650 nm) under high pressure. Raman and XRD measurements and theoretical calculations revealed significant enhancement in both interlayer and intralayer interactions during compression, leading to a remarkable modulation of the optoelectronic properties. By applying pressure, giant enhancement of photocurrent and tunable spectral response range were achieved in NiPS3, which provides a potential way to modify the optoelectronic properties for materials. [ABSTRACT FROM AUTHOR]

Photoelectric devices based on the photothermoelectric (PTE) effect show promising prospects for broadband detection without an external power supply. However, effective strategies are still required to regulate the conversion efficiency of light to heat and electricity. Herein, significantly enhanced photoresponse properties of PbI2 generated from a PTE mechanism via a high‐pressure strategy are reported. PbI2 exhibits a stable, fast, self‐driven, and broadband photoresponse at ≈980 nm. Intriguingly, the synergy of the photoconductivity and PTE mechanism is conducive to enhancing the photoelectric properties, and extending the detection bandwidth to the optical communication waveband (1650 nm) with an external bias. The dramatically enhanced photoresponse characteristics are attributed to narrowing of the band gap and a significantly decreased resistance, which originate from the enhancement of atomic orbital overlap owing to pressure‐induced Pb‐I bond contraction. These findings open up a new avenue toward designing self‐driven and broadband photoelectric devices. [ABSTRACT FROM AUTHOR]

Photoelectric devices based on the photothermoelectric (PTE) effect show promising prospects for broadband detection without an external power supply. However, effective strategies are still required to regulate the conversion efficiency of light to heat and electricity. Herein, significantly enhanced photoresponse properties of PbI2 generated from a PTE mechanism via a high‐pressure strategy are reported. PbI2 exhibits a stable, fast, self‐driven, and broadband photoresponse at ≈980 nm. Intriguingly, the synergy of the photoconductivity and PTE mechanism is conducive to enhancing the photoelectric properties, and extending the detection bandwidth to the optical communication waveband (1650 nm) with an external bias. The dramatically enhanced photoresponse characteristics are attributed to narrowing of the band gap and a significantly decreased resistance, which originate from the enhancement of atomic orbital overlap owing to pressure‐induced Pb‐I bond contraction. These findings open up a new avenue toward designing self‐driven and broadband photoelectric devices. [ABSTRACT FROM AUTHOR]