Understanding the molecular structure of HSW coal at atomic level:A comprehensive characterization from combined experimental and computational study

In this work,the coal samples from Hongshiwan(HSW)mining area,Ningxia,northwest of China,are characterized by using several modern materials characterization techniques,such as proximate and ultimate analyses,solid state 13C nuclear magnetic resonance(13C NMR),X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy(FT-IR).Then the key information about elements,valence,and chemical bonding for coal molecular structural construction is obtained.The results reveal that the main structure of HSW coal has 75.96%aromatic skeleton in mass.The ratio of aromatic bridge carbon to aromatic peripheral carbon of HSW coal is 0.315,indicating more naphthalene than benzene and anthracene in coal structures.Oxygen predominantly presents in the forms of ether(C–O),carbonyl(C=O)and carboxyl(–COO).Nitrogen presents in the forms of both pyridine and pyrrole.Methyl(–CH_(3))group is predominant in cyclic and aliphatic hydrocarbons.Based on obtained structural information and the approaches of average molecular structure,the single molecular formula of HSW coal is defined as C_(221)H_(148)O_(28)N_(2),with a molecular weight of 3142.32.Also,the 2D and 3D molecular model of HSW coal are built with computeraided modeling.The model is optimized and further verified by FT-IR and^(13)C NMR spectra simulation with quantum chemical calculations.Besides,a more complicated structure of complex model for HSW coal containing 10 single-molecules is also obtained.Therefore,molecular structure of HSW coal has been comprehensively depicted and understood at atomic level from both experimental and quantum chemical approaches in the current work.

Insights into the intrinsic interaction between series of C1 molecules and surface of NiO oxygen carriers involved in chemical looping processes

Understanding and modulating the interaction between various reactive molecules and oxygen carriers are the key issue to achieve process intensification of chemical looping technology.C1 chemical molecules play an important role in many reactions involved with chemical looping processes.However,up to now,there is still a lack of systematic and in-depth understanding of the adsorption mechanism of C1 molecules on the surface of oxygen carriers(OCs).In this work,the intrinsic interaction between a series of C1 molecules composed of CH4,CO,CO2,CH3OH,HCHO and HCOOH and surface of Ni O OCs in the chemical looping process have been studied using density functional theory calculations.Various adsorption configurations of C1 molecules and also different adsorption sites of Ni O have been considered.The structural features of stable configuration of C1 molecules on the surface of NiO OCs have been obtained.Further,the interacted sites,types and strengths of C1 molecules on the surface of NiO have been directly pictured by the independent gradient model methods.Also,the nature of the interaction between C1 molecule and Ni O surface has been investigated with the aid of energy decomposition analysis from a quantitative view.

Heterogeneity of clinical features, EEG and brain imaging findings in anti‑leucine‑rich glioma‑inactivated protein 1 autoimmune encephalitis: a retrospective case series study and review of the literature

Background Anti-leucine-rich glioma-inactivated 1(LGI-1)autoimmune encephalitis(AE),characterized by rapid decline of memory,seizures,and neuropsychiatric abnormalities,is a rare but devastating disorder.Early diagnosis and treatment are essential to prevent long-term sequelae.In this report,we provide a detailed description of clinical characteristics,laboratory test results,imaging,and electroencephalography(EEG)findings,as well as treatment responses of eight patients with anti-LGI-1 AE treated at our center.Case presentation At the onset,all eight patients presented with confusion/memory deterioration,seizures(including faciobrachial dystonic seizures or other types of seizure),and behavioral changes such as hallucination,paranoia,and anxiety.Four patients were found with severe hyponatremia.Anti-LGI1 antibodies were detected in the cerebrospinal fluid and/or serum of all patients.For patients with faciobrachial dystonic seizures,no discernible scalp EEG change was detected,while EEG recording of patients experiencing other types of seizure showed focal slowing,focal epileptiform discharges,and focal onset seizures.All patients showed abnormal brain magnetic resonance imaging signals,mainly involving the mesial temporal lobe and the hippocampus.In addition,one patient also experienced fulminant cerebral edema during the acute phase of the illness.All patients received immunotherapy and anti-seizure medications and achieved good seizure control.Nevertheless,these patients continued to experience cognitive impairment during their long-term follow-ups.Conclusions The care of anti-LGI1 AE patients requires rapid evaluation,prompt initiation of immunotherapy,and long-term follow-up.The long-term presence of neurocognitive complications observed in these patients underline the importance of developing reliable biomarkers that can distinguish between different subtypes of this disease with heterogeneous clinico-electrographico-radiological features.Further research is needed to understand the molecular mechanisms underlying the heterogeneity,in order to facilitate development of more effective treatments for anti-LGI1 AE.