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1.
J Environ Manage ; 330: 117164, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36603256

RESUMO

pH is one of the major parameters that influence the granulation and long-term operation of aerobic granular sludge (AGS). In hypersaline wastewater, the impact of pH on granulation and the extent of organic loading rate (OLR) that AGS can withstand under different pH are still not clear. In this study, AGS was cultivated at 3% salinity in three sequencing batch reactors with influent pH values of 5.0, 7.0, and 9.0, respectively, and the OLR was stepwise increased from 2.4 to 16.8 kg COD/m3·d after the granules maturation. The results showed the satisfactory granulation and organic removal under different influent pH conditions, in which the granulation was completed on day 43, 23, and 23, respectively. Neutral influent was the most appropriate for development of salt-tolerant aerobic granular sludge (SAGS), while acidic environment induced the formation of fluffy filamentous granules, and alkaline environment weakened the granule stability. Metagenomic analysis revealed the similar microbial community of neutral and alkaline conditions, with the predominance of genus Paracoccus_f__Rhodobacteraceae. While in acidic environment, fungus Fusarium formed the skeleton of filamentous granules and functioned as the carrier of bacteria including Azoarcus and Pararhodobacter. With the elevation of OLR, SAGSs were found to maintain the compact structure under OLRs of 2.4, 7.2, and 2.4 kg COD/m3·d, and obtain high TOC removal (>95.0%) under OLRs of 7.2, 14.4, and 14.4 kg COD/m3·d, respectively. For hypersaline high-strength organic wastewater, satisfactory TOC removal could also be obtained at broad pH ranges (5.0-9.0), in which neutral environment was the most suitable and acidic environment was the worst. This study contributed to a better understanding of SAGS granulation and treatment of hypersaline high-strength organic wastewater with different pH values.

2.
Environ Monit Assess ; 195(1): 230, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36571700

RESUMO

This study first assessed the pollution characteristics and probabilistic health risks of potentially hazardous elements (PHEs) in soils from the Dabaoding coal mining area in southwest China using Monte Carlo simulation. Experimental results showed that Cd was moderately enriched in soils, while Ni, Cr, and V were slightly enriched. However, the geoaccumulation index (Igeo) illustrated that the coal mining area had a low level of Cd pollution. PHEs produced a very high ecological risk to soils in the coal mining area, whereas Cd showed the highest contribution (82.56%). The mean hazard index of all soil PHEs was 7.45E - 02 and 4.18E - 01 for local adults and children, respectively, all of which were obviously lower than the maximum acceptable level of 1.0. However, Monte Carlo simulation analysis indicated that 1.08% of noncarcinogenic risk values for local children still exceeded the maximum acceptable level. Additionally, 10.84% and 18.40% of the total carcinogenic risk values for local adults and children, respectively, exceeded the threshold of 1E - 04. Indeed, Cr and Ni had the highest contributions to noncarcinogenic and carcinogenic risks, respectively. These findings suggest that Cd, Cr, and Ni should be identified as priority pollutants in coal mining areas. This study also provides valuable implications for policy-makers and environmental engineers, proposing efficient policies for better soil pollution control and remediation strategies in coal mining areas.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Solo , Metais Pesados/análise , Monitoramento Ambiental , Cádmio/análise , Poluentes do Solo/análise , Medição de Risco , Poluição Ambiental/análise , China , Carcinógenos/análise , Carvão Mineral/análise
3.
Nat Nanotechnol ; 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536044

RESUMO

Manipulation of solid-state spin coherence is an important paradigm for quantum information processing. Current systems either operate at very low temperatures or are difficult to scale up. Developing low-cost, scalable materials whose spins can be coherently manipulated at room temperature is thus highly attractive for a sustainable future of quantum information science. Here we report ambient-condition all-optical initialization, manipulation and readout of hole spins in an ensemble of solution-grown CsPbBr3 perovskite quantum dots with a single hole in each dot. The hole spins are initialized by sub-picosecond electron scavenging following circularly polarized femtosecond-pulse excitation. A transverse magnetic field induces spin precession, and a second off-resonance femtosecond-pulse coherently rotates hole spins via strong light-matter interaction. These operations accomplish near-complete quantum-state control, with a coherent rotation angle close to the π radian, of hole spins at room temperature.

4.
Plant Cell Environ ; 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36324267

RESUMO

Precocious leaf senescence can reduce crop yield and quality by limiting the growth stage. Melatonin has been shown to delay leaf senescence; however, the underlying mechanism remains obscure. Here, we show that melatonin offsets abscisic acid (ABA) to protect photosystem II and delay the senescence of attached old leaves under the light. Melatonin induced H2 O2 accumulation accompanied by an upregulation of melon respiratory burst oxidase homolog D (CmRBOHD) under ABA-induced stress. Both melatonin and H2 O2 induced the accumulation of cytoplasmic-free Ca2+ ([Ca2+ ]cyt ) in response to ABA, while blocking of Ca2+ influx channels attenuated melatonin- and H2 O2 -induced ABA tolerance. CmRBOHD overexpression induced [Ca2+ ]cyt accumulation and delayed leaf senescence, whereas deletion of Arabidopsis AtRBOHD, a homologous gene of CmRBOHD, compromised the melatonin-induced [Ca2+ ]cyt accumulation and delay of leaf senescence in Arabidopsis under ABA stress. Furthermore, melatonin, H2 O2  and Ca2+ attenuated ABA-induced K+ efflux and subsequent cell death. CmRBOHD overexpression and AtRBOHD deletion alleviated and aggravated the ABA-induced K+ efflux, respectively. Taken together, our study unveils a new mechanism by which melatonin offsets ABA action to delay leaf senescence via RBOHD-dependent H2 O2 production that triggers [Ca2+ ]cyt accumulation and subsequently inhibits K+ efflux and delays cell death/leaf senescence in response to ABA.

5.
J Am Chem Soc ; 144(42): 19372-19381, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36240390

RESUMO

In contrast to regular J- and H-aggregates, thin film squaraine aggregates usually have broad absorption spectra containing both J-and H-like features, which are favorable for organic photovoltaics. Despite being successfully applied in organic photovoltaics for years, a clear interpretation of these optical properties by relating them to specific excited states and an underlying aggregate structure has not been made. In this work, by static and transient absorption spectroscopy on aggregated n-butyl anilino squaraines, we provide evidence that both the red- and blue-shifted peaks can be explained by assuming an ensemble of aggregates with intermolecular dipole-dipole resonance interactions and structural disorder deriving from the four different nearest neighbor alignments─in sharp contrast to previous association of the peaks with intermolecular charge-transfer interactions. In our model, the next-nearest neighbor dipole-dipole interactions may be negative or positive, which leads to the occurrence of J- and H-like features in the absorption spectrum. Upon femtosecond pulse excitation of the aggregated sample, a transient absorption spectrum deviating from the absorbance spectrum emerges. The deviation finds its origin in the excitation of two-exciton states by the probe pulse. The lifetime of the exciton is confirmed by the band integral dynamics, featuring a single-exponential decay with a lifetime of 205 ps. Our results disclose the aggregated structure and the origin of red- and blue-shifted peaks and explain the absence of photoluminescence in squaraine thin films. Our findings underline the important role of structural disorder of molecular aggregates for photovoltaic applications.


Assuntos
Ciclobutanos , Análise Espectral , Vibração , Fenóis
6.
FEBS Lett ; 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36310378

RESUMO

For many inflammatory cytokines, the response elicited is dependent on the recruitment of the tumour necrosis factor receptor-associated factor (TRAF) family of adaptor proteins. All TRAF proteins have a trimeric C-terminal TRAF domain, while at the N-terminus most TRAFs have a RING domain that forms dimers. The symmetry mismatch of the N- and C-terminal halves of TRAF proteins means that when receptors cluster, it is presumed that RING dimers connect TRAF trimers to form a network. Here, using purified TRAF6 proteins, we provide direct evidence in support of this model, and we show that TRAF6 trimers bind Lys63-linked ubiquitin chains to promote their processive assembly. This study provides critical evidence in support of TRAF trimers as key players in signalling.

7.
Photoacoustics ; 28: 100411, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36254241

RESUMO

Optical-resolution photoacoustic microscopy offers high-resolution, label-free hemodynamic and functional imaging to many biomedical applications. However, long-standing technical barriers, such as limited field of view, bulky scanning probes, and slow imaging speed, have limited the application of optical-resolution photoacoustic microscopy. Here, we present freehand scanning photoacoustic microscopy (FS-PAM) that can flexibly image various anatomical sites. We develop a compact handheld photoacoustic probe to acquire 3D images with high speed, and great flexibility. The high scanning speed not only enables video camera mode imaging but also allows for the first implementation of simultaneous localization and mapping (SLAM) in photoacoustic microscopy. We demonstrate fast in vivo imaging of some mouse organs, and human oral mucosa. The high imaging speed greatly reduces motion artifacts and distortions from tissue moving, breathing, and unintended handshaking. We demonstrate small-lesion localization in a large region of the brain. FS-PAM offers a flexible high-speed imaging tool with an extendable field of view, enabling more biomedical imaging applications.

8.
J Phys Chem Lett ; 13(39): 9177-9185, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36169202

RESUMO

Luminescent solar concentrators (LSCs) have emerged as a disruptive technology that can potentially enable carbon-neutral buildings. The issues with current LSCs, however, are low optical efficiencies and limited long-term outdoor stability. Here we simultaneously address them by developing an LSC with aggregation-induced-emission (AIE) molecules embedded in a polydimethylsiloxane (PDMS) matrix. The AIE-emitter displayed a near unity emission quantum yield when embedded in the PDMS and the apparent absorption-emission Stokes shift reached 0.59 eV, effectively suppressing the reabsorption loss of waveguided photons inside an LSC. Moreover, the surface texture of the PDMS matrix was engineered using a bioinspired nanolithography method with a natural lotus leaf as the template. This allowed the fabricated AIE-PDMS LSC to inherit the superhydrophobic, self-cleaning properties of the leaf and meanwhile to possess a light-trapping capability. Our 100 cm2 LSC, when coupled with commercial Si PVs, delivered efficient solar power conversion, high visible transmittance, and high working stability.


Assuntos
Energia Solar , Carbono , Dimetilpolisiloxanos , Luminescência , Fótons
9.
Nat Commun ; 13(1): 5559, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36138041

RESUMO

Coherent interaction between matter and light field induces both optical Stark effect and Bloch-Siegert shift. Observing the latter has been historically challenging, because it is weak and is often accompanied by a much stronger Stark shift. Herein, by controlling the light helicity, we can largely restrict these two effects to different spin-transitions in CsPbI3 perovskite quantum dots, achieving room-temperature Bloch-Siegert shift as strong as 4 meV with near-infrared pulses. The ratio between the Bloch-Siegert and optical Stark shifts is however systematically higher than the prediction by the non-interacting, quasi-particle model. With a model that explicitly accounts for excitonic effects, we quantitatively reproduce the experimental observations. This model depicts a unified physical picture of the optical Stark effect, biexcitonic optical Stark effect and Bloch-Siegert shift in low-dimensional materials displaying strong many-body interactions, forming the basis for the implementation of these effects to information processing, optical modulation and Floquet engineering.

10.
Front Bioeng Biotechnol ; 10: 973141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35957646

RESUMO

We report a new 131I-labeling functional platform for targeted single-photon emission computed tomography (SPECT) imaging and radiotherapy of breast adenocarcinoma. In this study, polyethyleneimine (PEI) based nanogels (P.NH2 NGs) were prepared by water/oil polymerization, modified with targeted agent phenylboronic acid (PBA), and labeled with radionuclide 131I. The NGs without 131I-labeling own a spherical structure, uniform size distribution, and good cell viability. After 131I-labeling, the obtained 131I-PBA-PHP NGs displayed much higher cellular uptake than the non-targeted NGs due to the good softness and fluidity of NGs and the PBA targeting. The in vivo results demonstrated that 131I-PBA-PHP NGs could specifically target breast cancer cells and efficiently aggregate into xenograft breast adenocarcinoma for tumor SPECT imaging and specific radiotherapy. The developed 131I-labeling NGs may be used as a promising platform for efficient radioactive theranostic nanoplatform of tumor.

11.
ACS Appl Mater Interfaces ; 14(32): 36656-36667, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35925802

RESUMO

The nickel-rich cathode LiNi0.8Co0.1Mn0.1O2 (NCM811) is deemed as a prospective material for high-voltage lithium-ion batteries (LIBs) owing to its merits of high discharge capacity and low cobalt content. However, the unsatisfactory cyclic stability and thermostability that originate from the unstable electrode/electrolyte interface restrict its commercial application. Herein, a novel electrolyte composed of a polyethylene (PE) supported poly(vinylidene fluoride-co-hexafluoropropylene) (P(VdF-HFP)) based gel polymer electrolyte (GPE) strengthened by a film-forming additive of 3-(trimethylsilyl)phenylboronic acid (TMSPB) is proposed. The porous structure and good oxidative stability of the P(VdF-HFP)/PE membrane help to expand the oxidative potential of GPE to 5.5 V compared with 5.1 V for the liquid electrolyte. The developed GPE also has better thermal stability, contributing to improving the safety performance of LIBs. Furthermore, the TMSPB additive constructs a low-impedance and stable cathode electrolyte interphase (CEI) on the NCM811 cathode surface, compensating for GPE's drawbacks of sluggish kinetics. Consequently, the NCM811 cathode matched with 3% TMSPB-containing GPE exhibits remarkable cyclicity and rate capability, maintaining 94% of its initial capacity after 100 cycles at a high voltage range of 3.0-4.35 V and delivering a capacity of 133.5 mAh g-1 under 15 C high current rate compared with 68% and 75.8 mAh g-1 for the one with an additive-free liquid electrolyte. By virtue of the enhanced stability of the NCM811cathode, the cyclability of graphite||NCM811 full cell also increases from 48 to 81% after 100 cycles. The incorporation of P(VdF-HFP)-based GPE and TMSPB electrolyte additive points out a viable and convenient pathway to unlock the properties of high energy density and satisfactory safety for next-generation LIBs.

12.
Luminescence ; 37(9): 1541-1546, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35816184

RESUMO

Rapid ultrasensitive detection of trace polycyclic aromatic hydrocarbons (PAHs) is essential and significant for pollution control due to their hazard, persistence, and the wide distribution in the environment. Therefore, rapid detection of PAHs is critical for controlling pollution and protecting the ecology. Considering the advantages of surface-enhanced Raman spectroscopy (SERS), a simple and reliable SERS method was proposed in this work for detecting PAHs in water. Three chemicals, namely NaCl, KBr, and KI, were chosen to modify Ag nanoparticles (NPs) for phenanthrene (Phe) detection, and Ag NPs modified with KBr (Ag-Br NPs) showed the best SERS response. The mixing sequence and the concentration of KBr were optimized. The addition order of mixing KBr and Ag NPs before Phe solution was the best sequence, and the optimal concentration of KBr was 20 mM. Under optimal conditions, the limits of quantification for Phe, pyrene (Pyr), and anthracene (Ant) were 10-6  M, 10-7  M, and 10-7  M, respectively. Mixed PAHs (Phe, Pyr, and Ant) in spiked water samples were identified and quantified successfully. The proposed method has good application prospects in environmental pollution monitoring.


Assuntos
Nanopartículas Metálicas , Hidrocarbonetos Policíclicos Aromáticos , Antracenos , Brometos , Halogênios , Nanopartículas Metálicas/química , Compostos de Potássio , Pirenos , Prata/química , Análise Espectral Raman/métodos , Água
13.
Scand J Gastroenterol ; : 1-7, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35850581

RESUMO

OBJECTIVES: Limited literature exists on the characteristics of early gastric signet ring cell carcinoma (GSRCC) within 20 mm. This study aimed to explore this type of cancer from several aspects, to provide guidance for early detection and intervention of GSRCC. METHODS: We retrospectively collected data from 24 patients diagnosed with early GSRCC ≤20 mm in Beijing Friendship Hospital from 2016 to 2021. According to tumor size, those lesions were divided into three groups: diminutive group (1-5 mm, n = 4), small group (6-10 mm, n = 12) and intermediate group (11-20 mm, n = 8). The clinicopathologic and endoscopic characteristics of GSRCC were compared among the three groups. RESULTS: Treatment strategies for lesions differed according to the size (p<.05). There were no significant differences among the three groups with regard to age, sex, Helicobacter pylori infection, tumor location and macroscopic type. Lesions were often flat type and more likely to present with discoloration, uneven color, ulceration and submucosal invasion with the increase of diameter. Almost all cases showed abnormal intervening part (IP) under magnifying endoscopy. CONCLUSIONS: The location of early signet ring cell carcinoma is not specific, and the diminutive lesions are often flat. Abnormal IP may be the early endoscopic feature of early GSRCC.

14.
Photoacoustics ; 27: 100379, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35722270

RESUMO

Photoacoustic microscopy uses multiple wavelengths to measure concentrations of different absorbers. The speed of sound limits the shortest wavelength switching time to sub-microseconds, which is a bottleneck for high-speed broad-spectrum imaging. Via computational separation of overlapped signals, we can break the sound-speed limit on the wavelength switching time. This paper presents a new signal unmixing algorithm named two-step proximal gradient descent. It is advantageous in separating multiple wavelengths with long overlapping and high noise. In the simulation, we can unmix up to nine overlapped signals and successfully separate three overlapped signals with 12-ns delay and 15.9-dB signal-to-noise ratio. We apply this technique to separate three-wavelength photoacoustic images in microvessels. In vivo results show that the algorithm can successfully unmix overlapped multi-wavelength photoacoustic signals, and the unmixed data can improve accuracy in oxygen saturation imaging.

15.
Front Bioeng Biotechnol ; 10: 919235, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35733530

RESUMO

Hepatic carcinoma is one of the most common cancers worldwide, while its treatment remains a great challenge. Traditional therapeutic methods often have disadvantages such as limited therapeutic efficacy and potential side effects. In this study, we report the construction of bovine serum albumin (BSA)-stabilized manganese oxide (MnO2)/semiconducting polymer (SP) nanocomposites to combine photothermal therapy (PTT) and chemodynamic therapy (CDT) for treatment of hepatic carcinoma in living mouse models. Such nanocomposites are composed of BSA, SP, and MnO2 as the stabilizer, PTT, and CDT agent, respectively. SP produced local heat under near-infrared (NIR) laser irradiation for PTT, and MnO2 nanoparticles mediated CDT in the tumor microenvironment, leading to apoptosis of cancer cells. Such nanocomposite-mediated combinational therapy showed a much higher efficacy in inhibiting growth of subcutaneous HepG2 tumors in nude mice than sole treatment. This study thus provides a multifunctional nanoplatform for safe and effective treatment of hepatic carcinoma.

16.
Quant Imaging Med Surg ; 12(6): 3104-3114, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35655839

RESUMO

Background: Early pathologic studies have reported that focal areas of gray lesions in the cortex and other gray matter (GM) regions are important in multiple sclerosis (MS) patients. Quantitative magnetic resonance imaging (qMRI) can provide more specific insight into the disease process, progression, and therapeutic response of MS. The purpose of this study was to quantitatively assess the changes of global GM volumetry and relaxometry information simultaneously in MS patients using synthetic MRI. Methods: All MS patients and healthy controls (HCs) were recruited. The Expanded Disability Status Scale (EDSS) scores were obtained from all patients to evaluate the disability progression. Volumetry and relaxometry of the global brain and regional GM were obtained. The quantitative parameters between MS patients and HCs were compared using an analysis of covariance (ANCOVA). The Pearson correlation assessed the correlations between the quantitative parameters and EDSS, illness duration, education in MS patients. Results: Thirty-five MS patients and fifty-two age-matched HCs were enrolled in this prospective case-control study. The global volumetry including white matter volume (WMV), myelin volume (MYV), and brain parenchymal volume (BPV) were all significantly lower in MS patients (WMV: 613.120±65.388 vs. 579.903±68.432 mL; MYV: 151.883±22.766 vs. 192.457±27.381 mL; BPV: 1,136.771±106.126 vs. 1,276.712±107.368 mL), as well as a higher cerebral spinal fluid volume (CSFV) (241.294±81.805 vs. 177.017±39.729 mL) in MS patients than those in HCs. Similarly, brain parenchymal fraction (BPF) and myelin fraction (MYF) were significantly lower in MS patients (BPF: 82.623±5.368 vs. 87.85±2.392 mL; MYF: 11.034±1.529 vs. 13.231±1.465 mL). For regional GM volumetry, multiple regions of MS patients were significantly smaller than those of HCs (P<0.01, corrected). For regional GM relaxometry, the T1, T2, and PD values of multiple regions showed significant differences. Conclusions: These findings suggest that MS patients had global and regional brain volumetry and relaxometry alterations, and the synthetic MRI-derived parameters may be potentially used as specific quantitative markers for the clinic to improve the understanding of MS.

17.
Nanomaterials (Basel) ; 12(10)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35630880

RESUMO

Immunotherapy has emerged as one of the major strategies for cancer treatment. Unlike conventional therapeutic methods, immunotherapy can treat both primary and distant metastatic tumors through triggering systematic antitumor immune responses and can even prevent tumor recurrence after causing the formation of immune memory. However, immunotherapy still has the issues of low patient response rates and severe immune-related adverse events in clinical practices. In this regard, the combination of nanomedicine-mediated therapy with immunotherapy can modulate a tumor immunosuppressive microenvironment and thus amplify antitumor immunity. In particular, second near-infrared (NIR-II) photothermal therapy (PTT), which utilizes light conversions to generate heat for killing cancer cells, has shown unique advantages in combining with immunotherapy. In this review, the recent progress of engineering nanomedicines for NIR-II PTT combinational immunotherapy is summarized. The role of nanomedicine-mediated NIR-II PTT in inducing immunogenic cell death and reprogramming the tumor immunosuppressive microenvironment for facilitating immunotherapy are highlighted. The development of NIR-II-absorbing organic and inorganic nonmetal and inorganic metal nanomedicines for the NIR-II PTT combinational immunotherapy of cancer is also introduced in detail. Lastly, the current challenges and future perspectives of these nanomedicines for combinational immunotherapy are proposed.

18.
Curr Opin Struct Biol ; 74: 102381, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35537282

RESUMO

In recent decades, major progress has been made in the design of water-soluble proteins, yet the design of transmembrane proteins has lagged considerably. Despite their biological and pharmaceutical importance, only a limited number of transmembrane proteins have been successfully designed owing to the complexity of the membrane environment and difficulties in experimental characterization. Here, we introduce principles for transmembrane protein design in general and discuss design examples, including scaffold proteins and functional proteins. We also discuss how developments in design methods have advanced the field and what we may achieve with recent breakthroughs in structural biology.


Assuntos
Biologia Computacional , Proteínas de Membrana , Proteínas de Membrana/química
19.
Zhongguo Zhen Jiu ; 42(5): 559-62, 2022 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-35543949

RESUMO

"Unblocking fu organs" is one of the essential principles of Ma's warm moxibustion technique, characterized as "dredging" and "harmonizing" for either deficiency or excess condition. Under the guidance of this therapeutic thought, the acupoints for moxibustion are mainly selected from the middle and lower parts of the body. Regarding the therapeutic approach, the acupoint prescription for moxibustion should be formed in line with warming and promoting circulation of fu organs; the moxibustion degree should be specially considered, in which, the mild moxibustion is recommended to induce promoting action; and the systematic moxibustion technique should be the root for dredging fu organs and regulating zang organs. Ma's mild moxibustion technique stresses on removing the obstruction of fu organs and emphasizes promoting the qi activity of sanjiao (triple energizer) and regulating the balance of five zang organs.


Assuntos
Terapia por Acupuntura , Moxibustão , Pontos de Acupuntura , Etnicidade , Humanos , Hiperplasia , Moxibustão/métodos
20.
Langmuir ; 38(18): 5392-5403, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35439013

RESUMO

The rapid development of unconventional oil and gas resources presents challenges for foam flooding for reservoirs with high salinity and high heterogeneity at elevated temperatures. In this study, hydrophilic anionic sulfonate-modified nanoparticles (NPs) exhibited a synergistic effect with a cationic surfactant in stabilizing N2/water foam in the presence of concentrated divalent ions from ambient temperature up to 70 °C. With low concentrations of both the sulfonated NPs (SNPs) and cationic surfactant, the foams remained stable for 4 days at 50 °C and atmospheric pressure, while the surfactant-stabilized foams collapsed completely in 1 day. This stability mechanism of foams by the SNPs and cationic surfactant is described in terms of phase behavior, bulk shear rheology of the aqueous phase, and the dilational modulus of the gas-brine interface. The high surface elastic dilational modulus E' observed upon addition of the SNP provided stability against coarsening according to the Gibbs criteria. The cryo-SEM images also showed the compact bubble structure of foams provided by the SNPs. Consequently, very minor changes in the foam bubble size were observed at 208 bar (3000 psi) and 50 °C for up to 48 h with only 0.1 wt % or 0.3 wt % SNPs and 0.01 wt % Arquad 12-50, indicating excellent foam stability. The ability of the surfactant and NPs to stabilize foams at low concentrations broadens the application of foams in subsurface reservoirs at high temperatures and salinities.

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