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The inherently intermittent feature of solar energy requires reliable energy conversion and storage systems for utilizing the most abundant solar energy. Phase change materials are potential solutions to store a large amount of heat produced by solar light. However, few of the phase change materials have the ability to efficiently convert solar energy into heat; additionally, phase change materials need to be encapsulated in porous substrates for enhancing their leaking resistance and photo-to-thermal performance. In this work, monolithic MXene aerogels, fabricated by Al3+ cross-linking and freeze-drying, were used as the encapsulation and photothermal materials. The composites phase change materials of MXene/polyethylene glycol can be made with a large polyethylene glycol loading above 90 wt% with the maximum of 97 wt%, owing to the large porosity of MXene aerogels. The low content of MXene has a limited impact on the phase transition temperature and enthalpy of polyethylene glycol, with an enthalpy retention rate ranging from 89.2 to 96.5% for 90-97 wt% polyethylene glycol loadings. MXene aerogels greatly improve the leaking resistance of polyethylene glycol above its melting point of 60 °C, even at 100 °C. The composites phase change materials also show outstanding cycling stability for 500 cycles of heat storage and release, retaining 97.7% of the heat storage capability. The optimized composite phase change material has a solar energy utilization of 93.5%, being superior to most of the reported results. Our strategy produces promising composite phase change materials for solar energy utilization using the MXene aerogels as the encapsulation and photothermal materials.

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Efficient gas enrichment approaches are of great importance for the storage and transportation of clean energy and the sequestration of carbon dioxide. Of special interest is the regulated gas hydrate-based method; however, its operation requires adequate additives to overcome the low-storage capacity issue. Thus, this method is not economically feasible or environmentally friendly. In this work, a novel recyclable hydrate promoter of copolystyrene-sodium styrenesulfonate@Fe3O4 (PNS) nanoparticles with an integrated core-shell structure was synthesized through emulsion polymerization. This was found to effectively reduce the induction time of methane hydrate formation by one-third compared with the widely used sodium dodecyl sulfate (SDS); the corresponding gas storage capacity was also comparable, up to 155 v/v. In addition, the PNS nanoparticles showed a good performance in foam inhibition upon hydrate decomposition, which frequently occurred with the use of SDS and other surfactant-based promoters. In particular, the new promoters contributed to a more than 30% increase in CO2 storage capacity, coacting with the fine sediments that mimic a marine environment. This provided further possibilities of sequestering CO2 in the form a gas hydrate under the seafloor. The underlying mechanism was proposed to involve anchored surfactants on the surface and tiny channels between the nanoparticles that lead to rapid hydrate nucleation and controlled growth. The results showed that the integrated magnetically recovering nanoparticles developed in this study could improve the efficiency of gas storage by forming gas hydrates; the excellent recycling performance paved the way for solving the economic and environmental problems encountered in additive usage.

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Methane hydrate (MH) makes it possible to store methane using the cheapest and safest solvent: water. However, the sluggish formation kinetics hinders its practical utilization. Recently, the use of nanomaterials has been suggested as a potential solution; however, there is still a lack of high-efficiency kinetic promotors, and the promoting mechanism remains unclear. Herein, we demonstrated that MXene dispersion is promising for the storage of methane via MH with rapid formation kinetics, high storage capacity, and impressive cyclic stability. MXene can significantly shorten the induction time for MH formation. The enhanced kinetics was achieved by providing extra nucleation sites and enhancing thermal conductivity, although the increased surface tension of MXene dispersion could impede the MH formation via limited mass transfer. We confirmed that the concentration-dependent promoting effect of MXene dispersions results from regulating the assembly of water molecules. The insight of this work can apply to develop high-efficiency additives to control the formation kinetics of MH.

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Carbon nanotubes (CNTs) have been widely studied because of their potential applications. The increasing applications of CNTs and less known of their environmental fates rise concerns about their safety. In this study, the biotransformation of multi-walled carbon nanotubes (MWCNTs) by Labrys sp. WJW was investigated. Within 16 days, qPCR analysis showed that cell numbers increased 4.92 ± 0.36 folds using 100 mg/L MWCNTs as the sole carbon source. The biotransformation of MWCNTs, which led to morphology and functional group change, was evidenced by transmission electron microscopy and X-ray photoelectron spectroscopy analyses. Raman spectra illustrated that more defects and disordered carbon appeared on MWCNTs during incubation. The underlying biotransformation mechanism of MWCNTs through an extracellular bacterial Fenton-like reaction was demonstrated. In this bacteria-mediated reaction, the OH production was induced by reduction of H2O2 involved a continuous cycle of Fe(II)/Fe(III). Bacterial biotransformation of MWCNTs will provide new insights into the understanding of CNTs bioremediation processes.

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Carbon storage in the form of solid hydrate under seafloor has been considered to be promising for greenhouse gas control. Yet, open issues still remain on the role of the organic matters abundant in marine environments in the kinetics of hydrate formation; of particular interest is the involvement of the acid-dissolvable organic matters accompanying the acidification upon CO2 injection. In this work, the CO2 hydrate formation in the presence of the organic matters was in-situ monitored through the low-field nuclear magnetic resonance technique. It was found that the organic matters could kinetically promote the formation of CO2 hydrate; this effect was further enhanced by the sulfur-containing acid-dissolvable organic matters. Water in the large pores was preferentially consumed; the following water conversion facilitated by the organic matters would result in a fragmentation of the large pores into separated small pores isolated by the hydrate clusters. Consequently, a further enhancement of the gas-water contact is suggested as the existence of substantial hydrate patches could act as a mass transfer barrier. Our findings expand our understandings on the kinetics of CO2 hydrate formation in the presence of the organic matters and indicate the stability zone of gas hydrate a kinetically favorable geological setting for CO2 sequestration.

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Industrial processes emit enormous amounts of waste heat below 40 °C into the environment as it is cannot be used in other processes. Adsorption desalination can be driven by low-grade heat but has never been proven at temperatures below 40 °C as current adsorption materials require heat sources of 50-150 °C. Here, we present the first experimental study on adsorption desalination using a novel class of ionogel adsorption materials, which can be regenerated at 25 °C or a driving temperature difference of 5 °C. This outstanding property contrasts with the benchmarking silica gel, which requires heat sources of at least 50 °C. Ionogels are solid-state ionic materials retaining the sorption properties of the constituent ionic liquid. Thermodynamic vapor-liquid equilibrium data of water sorption on commercial ionic liquids reveal 1-ethyl-3-methylimidazolium acetate as the best fluid for this specific application. A full experimental characterization of the material is performed from imaging at the nanoscale to testing on a real adsorption desalinator. At 25 °C, the material achieves a specific daily water production of 6.7 kgwater/(kgionogel d), increasing to 17.5 kgwater/(kgionogeld) at 45 °C, outperforming silica gel by a factor of 2.

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Extensive efforts have been made regarding gas hydrate sample reconstruction in the laboratory for a better understanding and development of natural gas resources. Magnetic resonance imaging (MRI) is a useful method for directly observing the reconstruction of methane hydrate, yet relevant studies remain limited. In this study, a 9.4-T 400-MHz MRI instrument was employed to investigate CH4 hydrate formation in porous media involving various initial water saturation levels and sand diameters. Pressure histories and MRI signal variations were monitored to discuss the process of CH4 hydrate growth, and the three main formation stages of induction, rapid growth, and slow formation were determined. Furthermore, the liquid water performance in MRI micro-images was analyzed to predict the characteristics of CH4 hydrate formation. The results indicated that CH4 hydrate formed in a spatially and temporally random manner and that pore plugging occurred owing to the residual water encased in grown hydrate. Additionally, phase saturations, water conversion percentages, and formation rates were defined to evaluate the effect of sand diameter and initial water saturation on CH4 hydrate formation. With the reduction in the diameter of quartz glass beads from 400 µm to 100 µm, the average hydrate formation rate increased from 0.0010 min-1 to 0.0034 min-1, respectively. When the initial water saturation decreased to the optimized value (0.22 in this study), the water conversion percentage and hydrate saturation increased.

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An understanding of the nucleation and growth mechanism of methane hydrate in porous space is essential for exploitation and application of hydrates, but the mechanism is yet to be clarified. Magnetic resonance imaging (MRI) was employed to visually analyze the spatial and temporal formation behavior of methane hydrate in a porous media. Detailed information about the water distribution, initial nucleation sites, and hydrate growth was obtained, in addition to MRI images. The results demonstrated that the water molecules distributed in the vertical direction preferred the middle slice of a porous medium sample, and the decrease in the number of molecules in the middle slice and on both sides of the slice was similar during hydrate formation. The formation process are quite different in selected horizontal slices, which were contributed to the various distribution of water and gas in pore spaces and the randomness of methane hydrate formation. The extension of these predicted results could have important implications for optimizing the formation processes of gas hydrate in hydrate-based technologies.

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The role of the acupoint area collagen fibers in the efficacy of acupuncture lifting and thrusting (L&T) manipulation will be explored in this paper. 30 male NZW rabbits were randomly divided into 6 groups: sham operation group (Group N), model group (Group M), acupuncture without manipulation group (Group W), acupuncture L&T manipulation group (Group A), collagenase pretreatment group (Group JM), and collagenase pretreatment + acupuncture L&T manipulation group (Group JA). The bacterial endotoxin was used to generate the rabbit fever models. Acupuncture was applied at IL-11. The levels of IL-1ß, TNF-α, and IL-4 and the rectal temperature were measured at 2 h, 4 h, and 6 h after modeling and the collagen fiber morphology at acupoint area was observed after 6 hours. Results. As compared with Group N, the levels of IL-1ß and TNF-α in Group M were significantly higher; the level of IL-4 was significantly lower (P < 0.05). As compared with Group M, IL-1ß and TNF-α in Groups W and A were significantly lower and IL-4 was significantly higher (P < 0.05). As compared with Group W, IL-1ß and TNF-α in Group A were lower and IL-4 was higher (P < 0.05). The collagen fiber in Group A was slightly rough, distorted, and fractured. As shown in studies, the endotoxin-induced inflammatory response can be significantly inhibited by acupuncture whose efficacy can also be significantly improved by the manipulations. Collagenase pretreatment may be the first receptor to the mechanical force of the L&T manipulation.

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Objective. This study explored the mechanism of herb-partitioned moxibustion (HM) on dextran sulfate sodium- (DSS-) induced ulcerative colitis (UC) from the miRNA perspective. Methods. Rats were randomly divided into 3 groups [normal control (NC) group, UC model (UC) group, and herb-partitioned moxibustion (UCHM) group]. The UC and UCHM groups were administered 4% DSS for 7 days. The UCHM group received HM at the Tianshu (bilateral, ST25). The effect of HM on UC was observed and the miRNA expression profile in the colon tissues was analyzed. Results. Compared with the UC group, the body weights were significantly higher in the UCHM group on day 14 (P < 0.001); the macroscopic colon injury scores and microscopic histopathology scores in the UCHM group decreased (P < 0.05); and there were 15 differentially expressed miRNAs in the UCHM group. The changes in miR-184 and miR-490-5p expression levels on the UC were reversed by HM intervention. Validation using qRT-PCR showed that two miRNAs expression trend was consistent with the sequencing results. Conclusion. HM at ST25 might regulate miR-184 and miR-490-5p expression, act on the transcription of their target genes to regulate inflammatory signaling pathways, and attenuate inflammation and tissue injury in the colons of rats with DSS-induced UC.

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A novel hydrate-based method is proposed for separating heavy metal ions from aqueous solution. We report the first batch of experiments and removal characteristics in this paper, the effectiveness and feasibility of which are verified by Raman spectroscopy analysis and cross-experiment. 88.01-90.82% of removal efficiencies for Cr(3+), Cu(2+), Ni(2+), and Zn(2+) were obtained. Further study showed that higher R141b-effluent volume ratio contributed to higher enrichment factor and yield of dissociated water, while lower R141b-effluent volume ratio resulted in higher removal efficiency. This study provides insights into low-energy, intensive treatment of wastewater.

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The TLR2/NF-κB signaling pathway plays an important role in the pathomechanism of ulcerative colitis (UC); acupuncture and moxibustion can improve the damage in colonic tissues of UC, but the regulatory mechanism remains unknown. This study observed the effect of moxibustion on the TLR2/NF-κB signaling pathway at the Tianshu (ST25) and Qihai (CV6) acupuncture points in the UC rat. The result shows that TLR2, IRAK1, and IKK-b mRNA and protein levels in the colonic mucosa were significantly higher in the UC rats than in the control rats. Herb-partitioned moxibustion reduced the expression of TLR2, IRAK1, and IKK-b mRNA and proteins in the UC rats. Similarly, the expression of NF-κB was significantly increased and IFN-ß and IL-10 were significantly decreased in the colonic mucosa of UC rats, but herb-partitioned moxibustion reduced the expression of IFN-ß and upregulating the expression of IFN-ß and IL-10 significantly. It indicates that herb-partitioned moxibustion can inhibit the expression of multiple signaling molecules of the TLR2 pathway effectively, and it may modulate the excessive local immune response by inhibiting TLR2 signaling, thereby promoting the repair of damaged colonic mucosa.

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Through searching domestic and foreign medical journals in CNKI, Wanfang database, VIP database and Pubmed database from January of 2003 to November of 2013, 39 articles regarding musical electroacupuncture (MEA) were analyzed. The result showed that MEA was clinically used to treat neurological and psychotic disorders; because it was combined with musical therapy and overcame the acupuncture tolerability, and MEA was superior to traditional electroacupuncture. However, problems such as low research efficiency and the mechanism of MEA superiority and the musical specificity not being revealed by research design still exist. In future, large-sample multi-center RCT researches should be performed to clarify MEA clinical efficacy. With modern science and technology and optimized study design, guided by five-element theory of TCM, researches on different musical elements and characteristics of musical pulse current as well as MEA's correlation with meridians and organs should be studied, so as to make a further exploration on MEA mechanisms and broaden the range of its clinical application.

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The signal analysis of heart rate variability (HRV) has been very significant for heart disease of aided diagnosis, monitoring and evaluation. We proposed a new method of HRV signal analysis based on the Hilbert spectrum entropy dividing frequency range. According to Hilbert spectrum characteristics of the multi-resolution and the characteristic of HRV signal frequency spectrum, the Hilbert time-frequency spectrum entropy of HRV signal in different frequency range and the full frequency Hilbert time-frequency spectrum entropy with weighting factor were calculated. This approach was analyzed after the appropriate separation for various physiological factors based on the frequency range and it is more conducive to reflect the physiological and the pathological characteristics. Applying the new approach to the actual HRV signal of the MIT-BIH standard database, we obtained the results which showed that this method could effectively differentiate from the sample group for the young, the elder and the patients with atrial fibrillation, and for the sample group for the healthy persons and CHF patients, the performance in statistical analysis was superior to those of the general time-frequency entropy method. The approach could provide an effective analysis method for clinical HRV signal.

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According to the limitations of wavelet threshold in de-noising method, we approached a combining algorithm of the stationary wavelet transform with adaptive filter. The stationary wavelet transformation can suppress Gibbs phenomena in traditional DWT effectively, and adaptive filter is introduced at the high scale wavelet coefficient of the stationary wavelet transformation. It would remove baseline wander and keep the shape of low frequency and low amplitude P wave, T wave and ST segment wave of ECG signal well. That is important for analyzing ECG signal of other feature information.

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OBJECTIVE: To observe the effect of electroacupuncture (EA) on mitochondrial SDH and Na+ -K+ -ATPase activity, and lactate acid (LA) content in the peri-hemotoma tissue in rats with intracerebral hemorrhage (ICH) so as to explore its mechanisms in resisting cerebral ischemia. METHODS: A total of 80 Wistar rats were randomized into normal group, sham group, model group, EA group. The last three groups were further divided into 24 h, 72 h and 168 h subgroups respectively, with 8 cases in each group/subgroups. ICH model was established by caudatum-injection (right) of Collagense VII/heparini solution (2 microl). EA (2 Hz, 1 mA) was applied to "Baihui" (GV 20)-"Taiyang" (EX-HN 5) for 30 min. Chondriosome suspension of the cerebral perihemotoma tissue was got by gradient centrifugation for detecting SDH and Na+ -K+ -ATPase activity, and LA content with chromometry. RESULTS: In comparison with sham-operation group and control group, SDH and mitochondrial Na+ -K+ -ATPase activity in cerebral peri-hemotoma tissue declined significantly from 72 h and 24 h on respectively (P<0.05), while LA level increased markedly from 24 h on (P<0.05) in model group. Compared with sham-operation group, SDH activity (168 h) and Na+ -K+ -ATPase activity (24 h, 72 h and 168 h) in EA group also decreased significantly (P<0.05); LA level (24 h, 72 h) in EA group increased considerably (P<0.05). Whereas compared with model group, SDH and Na+ -K+ -ATPase activity increased significantly at most time courses (P<0.05), and LA level decreased remarkably (P<0.05) in EA group. CONCLUSION: EA can improve the energy metabolism, upregulate the activity of chondriosome,and reduce the accumulation of LA in the cerebral perihemotoma tissue of ICH rats.

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OBJECTIVE: To study the mechanism of scalp penetration acupuncture treating acute cerebral hemorrhage (ACH). METHODS: The treatment group (n = 30) and the control group (n = 30) were treated with the same basic therapy, but scalp penetration acupuncture was added to the treatment group. Changes of plasma ET and CGRP contents were compared. RESULTS: After treatment for 14 days, the content of plasma ET in the treatment group was significantly lower than that in the control group (P < 0.01). Moreover, the content of plasma CGRP was significantly higher than that in the control group (P < 0.01). CONCLUSION: Scalp penetration acupuncture is able to improve the prognosis of the patient with ACH by means of regulating the contents of plasma ET and CGRP.

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