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To reduce the fluctuation of the heat source water temperature and ambient temperature caused by variations in solar radiation, a solar absorption refrigeration system with a supplementary biomass combustion device for the office area of a factory was designed. A numerical model of the solar energy absorption refrigeration system based on the Aspen Plus software was developed. In particular, the effects of the heat source water temperature, condenser temperature, evaporation temperature, and dilute solution flow rate on the cooling capacity, coefficient of performance, unit equipment duty, and generator temperature during actual operation were investigated. The heat load of each piece of equipment in the unit were found to increase correspondingly with the increase of the heat source temperature when the evaporating temperature and condensing temperature are constant. The coefficient of performance of the unit decreased as the condensing temperature increased keeping the temperature of the heat source constant. The results demonstrated that the flow rate of the dilute solution has effects on the occurrence temperature, cooling capacity, and the unit performance coefficient.

The mineral laumontite can undergo hydration/dehydration reactions at room temperature. The hydration/dehydration produces a 3 to 6 percent volume change in the unit cell. The effects of laumontite hydration/dehydration on swelling and slake durability were investigated using altered granodiorite containing laumontite from the dam foundation of Yangfanggou Hydro Power Station, Sichuan, China. The occurrence of laumontite in altered rocks was first determined by petrological analysis. Typical samples were then collected for laboratory X-ray diffraction (XRD) analyses, free swelling tests, and slake durability index (SDI) tests. The test results were analyzed to determine the quantitative relationships between laumontite content, maximum axial strain, and slake durability index. We found that hydration of laumontite led to rock swelling. As laumontite content increased, maximum axial strain increased linearly; if water penetrated the rock quickly, swelling occurred over a short period. The hydration/dehydration of laumontite decreased slake durability of the rock; the SDI decreased approximately linearly as laumontite content increased.

Myocardial microenvironment plays a decisive role in guiding the function and fate of cardiomyocytes, and engineering this extracellular niche holds great promise for cardiac tissue regeneration. Platforms utilizing hybrid hydrogels containing various types of conductive nanoparticles have been a critical tool for constructing engineered cardiac tissues with outstanding mechanical integrity and improved electrophysiological properties. However, there has been no attempt to directly compare the efficacy of these hybrid hydrogels and decipher the mechanisms behind how these platforms differentially regulate cardiomyocyte behavior. Here, we employed gelatin methacryloyl (GelMA) hydrogels containing three different types of carbon-based nanoparticles: carbon nanotubes (CNTs), graphene oxide (GO), and reduced GO (rGO), to investigate the influence of these hybrid scaffolds on the structural organization and functionality of cardiomyocytes. Using immunofluorescent staining for assessing cellular organization and proliferation, we showed that electrically conductive scaffolds (CNT- and rGO-GelMA compared to relatively nonconductive GO-GelMA) played a significant role in promoting desirable morphology of cardiomyocytes and elevated the expression of functional cardiac markers, while maintaining their viability. Electrophysiological analysis revealed that these engineered cardiac tissues showed distinct cardiomyocyte phenotypes and different levels of maturity based on the substrate (CNT-GelMA: ventricular-like, GO-GelMA: atrial-like, and rGO-GelMA: ventricular/atrial mixed phenotypes). Through analysis of gene-expression patterns, we uncovered that the engineered cardiac tissues matured on CNT-GelMA and native cardiac tissues showed comparable expression levels of maturation markers. Furthermore, we demonstrated that engineered cardiac tissues matured on CNT-GelMA have increased functionality through integrin-mediated mechanotransduction (via YAP/TAZ) in contrast to cardiomyocytes cultured on rGO-GelMA.

Cd and Pb are a toxic environmental pollutant, and their elevated concentrations in the waters and soils could exert detriment effects on human health by food chain. In order to evaluate the capacity to heavy metal accumulation and the physiochemical responses of two Salix genotypes, a 35-day hydroponic seedling experiment was implemented with Salix matsudana Koidz. 'Shidi1' (A42) and Salix psammophila C. 'Huangpi1' (A94) under different concentrations of Cd (15 and 30 μM) or Pb (250 and 300 μM). The results showed that the biomass of A94 severely reduced more than that of A42. The accumulation ability of Cd in different plant organs followed the sequence of leaves > roots > stems. Pb primarily accumulated in the roots for both Salix genotypes (54.27 mg g-1 for A42 and 54.52 mg g-1 for A94). Translocation factors based on accumulation (TF') for Cd were more than 8.0, while TF's for Pb were less than 1.0 in both A42 and A94, implying they could be applied in the phytoremediation of Cd-contaminated sites due to their stronger ability to Cd phytoextraction. The stress of Cd or Pb significantly increased malondialdehyde (MDA) contents and increased photosynthetic rates in leaves of two Salix genotypes. Transpiration rates of willow were positively correlated with its Cd translocation. Both catalase (CAT) and peroxidase (POD) activities were suppressed, while the superoxide dismutase (SOD) was boosted with increasing Cd and Pb levels in the leaves and roots of the two willow genotypes, suggesting SOD plays an important role in the removal of ROS. The inconsistency of the changes in enzyme activity suggests that the integrated antioxidative mechanisms regulate the tolerance to Cd and Pb stress.

Methylated arsenic species, including monomethyl arsenate (MMA) and dimethyl arsenate (DMA), are frequently detected in natural waters due to the biochemical methylation of arsenic and various human activities. The presence of MMA/DMA may cause excess total arsenic (>10 μg/L) in drinking water, yet the efficient removal of methylated arsenic still remains challenging. Herein, we reported the utilization of a recently developed nanocomposite HZO@N201 for selective removal of MMA and DMA from water. HZO@N201 contains the gel-type anion exchanger N201, i.e., quaternary ammoniated poly(styrene-co-divinylbenzene) beads, as the host, and the embedded sub-5 nm hydrated zirconium oxide (HZO) for specific adsorption. In comparison with the commercially available nanocomposite HZO@D201, which was prepared through in-situ growth of HZO inside the macroporous anion exchanger D201, the adsorption capacities of HZO@N201 toward MMA and DMA ascended by ∼ 1.9 and ∼ 2.2 times, respectively, mainly benefitting from the sub-5 nm nature of HZO@N201. The competing anions including sulfate, chloride and bicarbonate exerted negligible impact on the removal efficiency toward MMA/DMA, due to inner-sphere complex formation between HZO NPs and MMA/DMA, as verified by SEM-EDS and XPS Zr 3d analysis. The exhausted HZO@N201 was fully regenerated by alkaline treatment for cyclic utilization without obvious efficiency loss. In fixed-bed experiments, HZO@N201 column was able to successively produce ∼ 4000 and ∼ 160 bed volume (BV) clean water from the feeding solutions containing MMA and DMA, while the values for HZO@D201 column were merely ∼ 1600 BV and ∼ 70 BV, respectively.

The available data in the munascript “Influence of operating conditions disturbances on refrigeration performance of a regenerative solar absorption refrigeration unit” are put in the file, including “Fig. 1 Solar radiation and air temperature curve in Qingzhou”, “Fig. 3 The actual operation of the system in a typical day”, “Fig. 7 Impact of heat source water temperature on COP and equipment duty”, “Fig. 8 (a) Impact of condenser temperature on COP”, “Fig. 8 (b) impact of evaporating temperature on cooling capacity and COP”, “Fig. 9 (a) Impact of dilute solution flow on generator temperature, hot water temperature”, and “Fig. 9 (b) Impact of dilute solution flow on cooling capacity and COP”.

With the continuous development of the demand of electric power users, the analysis of users' electric power consumption(EPS) is becoming more and more important. The frequency of data acquisition and the dimension of data analysis are increasing, which makes the analysis of EPS behavior more precise. The development of user tag and portrait technology brings a more intuitive and concise expression to the analysis of user's EPS. Based on massive user archives, power load and EPS data, considering the user's power consumption characteristics and influencing factors, a user behavior tag library is built, and k-means algorithm is used to tag clustering to achieve different types of EPS behavior. The tag clustering results of 2000 industrial and commercial users show that the selected tags of EPS behavior is reasonable and the clustering algorithm is effective. The research results of this paper can provide powerful data support for power companies to understand the user's EPS habits, mining user's electric power needs and improve the service level.

To create life-like movements, living muscle actuator technologies have borrowed inspiration from biomimetic concepts in developing bioinspired robots. Here, the development of a bioinspired soft robotics system, with integrated self-actuating cardiac muscles on a hierarchically structured scaffold with flexible gold microelectrodes is reported. Inspired by the movement of living organisms, a batoid-fish-shaped substrate is designed and reported, which is composed of two micropatterned hydrogel layers. The first layer is a poly(ethylene glycol) hydrogel substrate, which provides a mechanically stable structure for the robot, followed by a layer of gelatin methacryloyl embedded with carbon nanotubes, which serves as a cell culture substrate, to create the actuation component for the soft body robot. In addition, flexible Au microelectrodes are embedded into the biomimetic scaffold, which not only enhance the mechanical integrity of the device, but also increase its electrical conductivity. After culturing and maturation of cardiomyocytes on the biomimetic scaffold, they show excellent myofiber organization and provide self-actuating motions aligned with the direction of the contractile force of the cells. The Au microelectrodes placed below the cell layer further provide localized electrical stimulation and control of the beating behavior of the bioinspired soft robot.

With the explosive growth of user load data in power consumption information collection and load control systems, traditional computing frameworks and methods are faced with tremendous computational pressure when dealing with massive user load clustering and carrying out load characteristic analysis. In this paper, with a view to increasing accuracy and computational power of graphic process unit (GPU), the fast parallel K-means clustering algorithm is proposed based on Nvidia compute uniform device architecture (CUDA). This algorithm uses parallel speedup strategies, such as parallelization of computing distance between the data to be divided and the clustering center, parallelization of counting numbers of category changing curves, rational allocation of blocks, which greatly improves the clustering speed of the user load curve. A number of test examples show that K-means power load curve clustering algorithm based on CUDA proposed in this paper has a high speedup ratio and strong adaptability, which is a good way to solve the problem of massive load curve clustering.

In this study, a micro-EDM process of exceeded slender micro-shaft is proposed. It could be divided into two parts, rough machining and finish processing. In rough machining procedure, the micro-shaft feeds along the radial and motions periodically along axial direction. High machining voltage is adopted to improve machining efficiency. In finish machining procedure, the micro-shaft feeds along radial and motions along tangential direction. Low open voltage is adopted to improve surface quality and reduce explosive force. By combining rough machining and finish machining, a high surface-quality micro-shaft with a diameter of 25μm and high aspect ratio of 120:1 was fabricated.