A hybrid physics-informed data-driven neural network for CO_(2) storage in depleted shale reservoirs

To reduce CO_(2) emissions in response to global climate change,shale reservoirs could be ideal candidates for long-term carbon geo-sequestration involving multi-scale transport processes.However,most current CO_(2) sequestration models do not adequately consider multiple transport mechanisms.Moreover,the evaluation of CO_(2) storage processes usually involves laborious and time-consuming numerical simulations unsuitable for practical prediction and decision-making.In this paper,an integrated model involving gas diffusion,adsorption,dissolution,slip flow,and Darcy flow is proposed to accurately characterize CO_(2) storage in depleted shale reservoirs,supporting the establishment of a training database.On this basis,a hybrid physics-informed data-driven neural network(HPDNN)is developed as a deep learning surrogate for prediction and inversion.By incorporating multiple sources of scientific knowledge,the HPDNN can be configured with limited simulation resources,significantly accelerating the forward and inversion processes.Furthermore,the HPDNN can more intelligently predict injection performance,precisely perform reservoir parameter inversion,and reasonably evaluate the CO_(2) storage capacity under complicated scenarios.The validation and test results demonstrate that the HPDNN can ensure high accuracy and strong robustness across an extensive applicability range when dealing with field data with multiple noise sources.This study has tremendous potential to replace traditional modeling tools for predicting and making decisions about CO_(2) storage projects in depleted shale reservoirs.

Probiotics in Helicobacter pylori eradication therapy: A systematic review and meta-analysis

AIM: To summarize the evidence from randomized controlled trials(RCTs) regarding the effect of probiotics by using a meta-analytic approach.METHODS: In July 2013, we searched PubM ed, EMBASE, Ovid, the Cochrane Library, and three Chinese databases(Chinese Biomedical Literature Database, Chinese Medical Current Content, and Chinese Scientific Journals database) to identify relevant RCTs.We included RCTs investigating the effect of a combination of probiotics and standard therapy(probiotics group) with standard therapy alone(control group).Risk ratios(RRs) were used to measure the effect of probiotics plus standard therapy on Helicobacter pylori(H.pylori) eradication rates, adverse events, and patient compliance using a random-effect model.RESULTS: We included data on 6997 participants from 45 RCTs, the overall eradication rates of the probiotic group and the control group were 82.31% and 72.08%, respectively.We noted that the use of probiotics plus standard therapy was associated with an increased eradication rate by per-protocol set analysis(RR = 1.11; 95%CI: 1.08-1.15; P < 0.001) or intention-totreat analysis(RR = 1.13; 95%CI: 1.10-1.16; P < 0.001).Furthermore, the incidence of adverse events was 21.44% in the probiotics group and 36.27% in the control group, and it was found that the probiotics plus standard therapy significantly reduced the risk of adverse events(RR = 0.59; 95%CI: 0.48-0.71; P < 0.001), which demonstrated a favorable effect of probiotics in reducing adverse events associated with H.pylori eradication therapy.The specific reduction in adverse events ranged from 30% to 59%, and this reduction was statistically significant.Finally, probiotics plus standard therapy had little or no effect on patient compliance(RR = 0.98; 95%CI: 0.68-1.39; P = 0.889).CONCLUSION: The use of probiotics plus standard therapy was associated with an increase in the H.pylori eradication rate, and a reduction in adverse events resulting from treatment in the general population.However, this therapy did not improve patient compliance.

Evolution mechanism of recrystallization in a nickel-based single crystal superalloy under various cooling rates during heat treatment

The recrystallization behaviors of a nickel-based single crystal superalloy during heat treatment at 1,200℃ for 4 h with various cooling rates were studied.Results show that the thickness of recrystallization layer decreases with the increase of cooling rate.In addition,the microstructures ofγ′phase in the recrystallization region are different in various cooling rates.In the high cooling rates(70,100℃·min^(-1)),small size and high volume fraction ofγ′phases are formed in the recrystallization region.It is also found that irregular fine secondaryγ′phases are precipitated between matrix channels with an average size of 150 nm in the original matric(100℃·min^(-1)).The sizes of the secondaryγ′phase decrease with the increase of cooling rate.In contrast,large size and small volume fraction ofγ′phases are formed in the recrystallization region,and a grain boundary layer is formed under a low cooling rate(10℃·min^(-1)).The evolution mechanism of recrystallization at various cooling rates during heat treatment is analyzed.

Dependence of the length of solar filament threads on the magnetic configuration

High-resolution Ha observations indicate that filaments consist of an as- sembly of thin threads. In quiescent filaments, the threads are generally short, whereas in active region filaments, the threads are generally long. In order to explain these observational features, we performed one-dimensional radiative hydrodynamic sim- ulations of filament formation along a dipped magnetic flux tube in the framework of the chromospheric evaporation-coronal condensation model. The geometry of a dipped magnetic flux tube is characterized by three parameters, i.e., the depth （D）, the half-width （w） and the altitude （h） of the magnetic dip. A survey of the parame- ters in numerical simulations shows that when allowing the filament thread to grow in 5 days, the maximum length （Lth） of the filament thread increases linearly with w, and decreases linearly with D and h. The dependence is fitted into a linear function Lth = 0.84w --0.88D - 2.78h ＋ 17.31 （Mm）. Such a relation can qualitatively explain why quiescent filaments have shorter threads and active region filaments have longer threads.

MHD Seismology of a loop-like filament tube by observed kink waves

We report and analyze observational evidence of global kink oscillations in a solar filament as observed in Ha by instruments administered by National Solar Observatory （NSO）/Global Oscillation Network Group （GONG）. An M1.1-class flare in active region （AR） 11692 occurred on 2013 March 15 and induced a global kink mode in the filament lying towards the southwest of AR 11692. We find periods of about 61-67 minutes and damping times of 92-117 minutes at positions of three ver- tical slices chosen in and around the filament apex. We find that the waves are damped. From the observed period of the global kink mode and damping timescale using the theory of resonant absorption, we perform prominence seismology. We estimate a lower cut-off value for the inhomogeneity length scale to be around 0.34-0.44 times the radius of the filament cross-section.