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Petroleum Science 2022年第6期19卷 3107-3115页

作者： Qiang Chen Hui-Jie Yang He Liu Yi Liu dong-feng zhao State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of Petroleum(East China)QingdaoShandong 266580China Department of Energy Conservation and Cleaner Production Qingdao OASIS Environmental&Safety Technology Co.LtdQingdaoShandong 266555China

Mild thermal treatment is an important partial upgrading technique to enable bitumen pipeline transportation,but no attention has been paid to the impact of mild thermal treatment on the emulsification behavior of emerging partially upgraded *** compounds are active emulsion stabilizers in bitumen *** emulsion stabilizing capacity of bitumen asphaltenes was investigated,before and after a mild thermal treatment at 400℃.The structural morphology and mechanical property of the asphaltene interfacial films were analyzed by using a combination of cryo-SEM,Langmuir trough,and Brewster angle *** thermal treatment significantly enhanced the emulsion stabilizing capacity of bitumen asphaltenes;the interfacial films formed by the thermally treated asphaltene samples appeared to be rougher and thicker with more abundant micron-scale wrinkle *** interfacial corrugation may intensify the mechanical stability/flexibility of the asphaltene films and consequently strengthen the stability of emulsion droplet.

关键词： Asphaltenes Interfacial film Emulsion stabilizing capacity Mild thermal treatment

An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： Na-Xia Yang Guo-Fa Li Ting-Hui Li dong-feng zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Dagang Branch Research InstituteBGPTianjin300280China

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural *** intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic ***,the extensive demand for training data imposes limitations on their wider *** overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training ***,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader *** seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies *** analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image ***,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic *** approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function

Model-constrained and data-driven double-supervision acoustic impedance inversion

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Petroleum Science 2023年第5期20卷 2809-2821页

作者： dong-feng zhao Na-Xia Yang Jin-Liang Xiong Guo-Fa Li Shu-Wen Guo State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Dagang Oil Field PetroChinaTianjin300280China Research Institute of Exploration and Development Dagang Oil FieldPetroChinaTianjin300280China

Seismic impedance inversion is an important technique for structure identification and reservoir ***-based and data-driven impedance inversion are the commonly used inversion *** practice,the geophysical inversion problem is essentially an ill-posedness problem,which means that there are many solutions corresponding to the same seismic ***,regularization schemes,which can provide stable and unique inversion results to some extent,have been introduced into the objective function as constrain *** them,given a low-frequency initial impedance model is the most commonly used regularization method,which can provide a smooth and stable ***,this model-based inversion method relies heavily on the initial model and the inversion result is band limited to the effective frequency bandwidth of seismic data,which cannot effectively improve the seismic vertical resolution and is difficult to be applied to complex structural ***,we propose a data-driven approach for high-resolution impedance inversion based on the bidirectional long short-term memory recurrent neural network,which regards seismic data as time-series rather than image-like *** with the model-based inversion method,the data-driven approach provides higher resolution inversion results,which demonstrates the effectiveness of the data-driven method for recovering the high-frequency ***,judging from the inversion results for characterization the spatial distribution of thin-layer sands,the accuracy of high-frequency components is difficult to ***,we add the model constraint to the objective function to overcome the shortages of relying only on the data-driven ***,constructing the supervisor1 based on the bidirectional long short-term memory recurrent neural network,which provides the predicted impedance with higher ***,convolution constraint as supervisor2 is introduced into the objective fu

关键词： Acoustic impedance inversion Model constraints Double supervision BiLSTM neural network Reservoir structure characterization

Spin-orbit Splitting and Lifetime Broadening in the A2△ Electronic State of l-C5H

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Chinese Journal of Chemical Physics 2012年第2期25卷 129-134,I0003页

作者： Mohammad Ali Haddad dong-feng zhao Harold Linnartz Wim Ubachs Institute for Lasers Life and Biophotonics VU University Amsterdam De Boelelaan 1081 NL1081HV Amsterdam the Netherlands Sackler Laboratory for Astrophysics Leiden Observatory University of Leiden PO Box 9513 NL2300 RA Leiden the Netherlands

Optical absorption bands at -18772 and -18807 cm-1, previously assigned to A2A-X2H electronic origin band transitions of the linear carbon-chain radicals CsH and CsD, respectively, have been reinvestigated. The spectra have been recorded in direct absorption applying cavity ring-down spectroscopy to a supersonically expanding acetylene/helium plasma. The improved spectra allow deducing a l-CsH upper state spin-orbit coupling constant X=-0.7（3） cm-1 and a A2A lifetime of 1.65=0.3 ps.

关键词： Cavity ring down spectroscopy Carbon-chain radical Interstellar molecule CsH

Imaging the [1+1] Two-Photon Dissociation Dynamics of Br2 + in a Cold Ion Beam

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Chinese Journal of Chemical Physics 2019年第5期32卷 531-535页

作者： Hao Liang Zheng-fang Zhou Ze-feng Hua Yun-xiao zhao Shao-wen feng Yang Chen dong-feng zhao Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

The [1+1] two-photon dissociation dynamics of mass-selected 79Br2 + has been studied in a cold ion beam using a cryogenic cylindrical ion trap velocity map imaging spectrometer. The quartet 14Σ- u;3=2 state of 79Br2 + is employed as an intermediate state to initiate resonance enhanced two-photon excitation to high-lying dissociative states in the 4.0-5.0 eV energy region above the ground rovibronic state. Total kinetic energy release (TKER) and the twodimensional recoiling velocity distributions of fragmented 79Br+ ions are measured using the technique of DC-slice velocity map imaging. Branching ratios for individual state-resolved product channels are determined from the TKER spectra. The measured photofragment angular distributions indicate that the dissociation of 79Br2 + occurs in dissociative Ω=3/2 state via ΔΩ=0 parallel transition from the 14Σ-u;3=2 intermediate state. Due to the considerable spin-orbit coupling effects in the excited states of 79Br2 +, higher-lying dissociative quartet states are likely responsible for the observed photodissociation processes.

关键词： Photodissociation dynamics Br2+ Velocity map imaging Ion trap

Photodissociation Dynamics of OCS at 207 nm:S(1D2)+CO(X^1Σ^+)Product Channel

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Chinese Journal of Chemical Physics 2020年第3期33卷 291-295,I0002页

作者： Xi-lin Bai dong-feng zhao Yang Chen School of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004China Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical Physicsand Synergetic Innovation Center of Quantum Information&Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China

By using the direct current slice velocity map imaging technique,the polarization experiment for S(1D2)product from the ultraviolet photodissociation of carbonyl sulfide at 207 nm was *** angular momentum polarization character of the photofragment S(1D2)was detected via two different resonance enhanced multiphoton ionization intermediate states,1F3 and 1P1,and four different pump-probe laser polarization *** angular distribution of the corresponding CO(X^1Σ^+)coproducts was extracted and analyzed using the molecular-frame polarization and the laboratory-frame anisotropy *** observed total kinetic energy release spectrum indicates that there are three dissociation channels,corresponding to the low,medium,and high kinetic *** sources of the low and medium kinetic energy channels are consistent with those of bimodal translational energy distribution at longer photolysis *** high kinetic energy channel is a new dissociation channel arising from the direct dissociation from the single repulsive A(2^1A′)state.

关键词： Photodissociation dynamics Carbonyl sulfide Velocity map imaging

Predictive value of D-dimer for portal vein thrombosis after portal hypertension surgery in hepatitis B virus-related cirrhosis

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World Journal of Gastroenterology 2007年第48期13卷 6588-6592页

作者： Mei-Hai Deng Bo Liu He-Ping Fang Wei-dong Pan zhao-feng Tang Peng Deng Yue-Si Zhong Rui-Yun Xu Department of Hepato-biliary Surgery Third Affiliated Hospital Sun Yat-Sen University Guangzhou 510630 Guangdong Province China

AIM: To evaluate the predictive value of D-dimer as a predictive indicator of portal vein thrombosis (PVT) after portal hypertension surgery in hepatitis B virus-related cirrhosis. METHODS: A prospective study was carried out in 52 patients who had undergone surgery for portal hypertension in hepatitis B virus-related cirrhosis. Changes in perioperative dynamic D-dimer were observed. The sensitivity, specifi city, positive predictive values and negative predictive values of D-dimer were calculated, and ROC curves were analyzed. RESULTS: The D-dimer levels in the group developing postoperative PVT was signifi cantly higher than those in the group not developing PVT (P = 0.001), and the ROC semi-quantitative and qualitative analysis of D-dimer showed a moderate predictive value in PVT (semi- quantitative value Az = 0.794, P = 0.000; qualitative analysis: Az = 0.739, P = 0.001). CONCLUSION: Dynamic monitoring of D-dimer levels in patients with portal hypertension after surgery can help early diagnosis of PVT, as in cases where the D-dimer levels steadily increase and exceed 16 μg/mL, the possibility of PVT is very high.

关键词： Portal hypertension Portal vein thrombosis Splenectomy D-dimer Diagnosis

Two-state energy model and experimental study of coal adsorb methane

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 488-492页

作者： Zeng-Chao feng dong zhao Zhi-Xiang LIU Yan-Qi WANG Hong-Qiang GOU Mining Technology Institute Taiyuan University of Technology Taiyuan 030024 China

There are two states of methane existing in coal, free methane and adsorptive methane. The two states of methane exchanged with each other which need the energy exchange with outside. It is released heat when methane adsorption on coal, instead of absorbed heat. According to the gas molecules Boltzmann energy distribution, is obtained the equilibrium equations of the two states of methane in coal, as well as the heat of adsorption equation when exchanged into each other. At the same time, high temperature experiments of methane adsorption on coal have been certificated to the theoretical model. At last the experimental results presented that： the two-state energy model could be accurately described the distribution of the two states of methane in the coal; the adsorption heat is related to the initial equilibrium state of methane adsorption; the adsorption heats are different with different coal ranks.

关键词： two-state energy model adsorption heat chemical potential experimental study

Ion-Neutral Photofragment Coincidence Imaging of Photodissociation Dynamics of Ionic Species

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Chinese Journal of Chemical Physics 2021年第1期34卷 81-86,I0011,I0012页

作者： Ze-feng Hua Yun-xiao zhao You-qing Li Gao-ming Hu Yang Chen dong-feng zhao CAS Center for Excellence in Quantum Information and Quantum Physics Hefei National Laboratory for Physical Sciences at the Microscaleand Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China

The recen tly cons true ted cryogenic cylindrical ion trap velocity map imaging spectrometer(CIT-VMI)has been upgraded for coincidence imaging of both ionic and neutral photofragments from photodissociation of ionic *** prepared ions are cooled down in a homemade cryogenic cylindrical ion trap and then extracted for photodissociation *** th the newly designed elec trie fields for extraction and acceleration,the ion beam can be accelerated to more than 4500 eV,which is necessary for velocity imaging of the neutral photofragments by using the position-sensitive imaging detect *** setup has been tested by the 355 nm pho todissocia tion dynamics of the argon dimer cat ion(Ar2+).From the recorded experimen tal images of both neu tral Ar and ionic Ar+fragments,we interpret velocity resolutions of△v/vu4.6%for neutral fragments,and△v/vul.5%for ionic fragments,respectively.

关键词： Ion trap Velocity map imaging photofragment coincidence imaging

Tonifying Shen-Yin and-Yang Principles in Treating Osteoporosis: All Roads Lead to Rome

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World Journal of Traditional Chinese Medicine 2016年第4期2卷 38-48页

作者： Wei Gou Nan-Mei Liu Cheng-Long Wang Hui-Ling Wang Shi Lu dong-feng zhao Xiu-Zhi Yu Department of Dialysis the 455th Hospital of People's Liberation Army of China Shanghai 200052 China Department of Nephrology the 455th Hospital of People's Liberation Army of China Shanghai 200052 China Longhua Hospital Shanghai University of Traditional Chinese Medicine Shanghai 200032 China

Tonifying Shen strategy works as an important alternative and complementary method that is widely used to treat osteoporosis in Traditional Chinese Medicine(TCM) based on the proper identification of Zheng. Shen deficiency Zheng is one of the main types of osteoporosis while Shen-Yin and-Yang deficiencies represent two basic principles/types of Shen deficiency. Currently, Tonifying Shen strategy, in particular, the Tonifying Shen-Yin and-Yang principles, has been demonstrated to exert osteoprotective effects. However, the mechanisms by which Tonifying Shen strategy and/or Tonifying Shen-Yin and-Yang principles function in treating osteoporosis are still not clearly understood. Here we first briefly explore current understanding of Tonifying Shen strategy, such as Tonifying Shen prescriptions, herbs, and effective components, in treating osteoporosis. Furthermore, the mechanism of Tonifying Shen-Yang principle in treating osteoporosis is reviewed from the clinic experience, animal, and mechanistic investigation. Moreover, the mechanisms by which Tonifying Shen-Yin principle in treating osteoporosis are established. Finally, we compare the similarity and difference between Tonifying Shen-Yang and-Yin principles in treating *** findings indicate that both principles exert bone-protective effects in treating osteoporosis by simultaneously stimulating the differentiation of mesenchymal stem cells(MSCs) into osteoblast and the differentiation of hematopoietic stem cells(HSCs) into osteoclast. However,Tonifying Shen-Yin principle is in favor of increasing bone mineral density(BMD) while Tonifying Shen-Yang principle is in favor of osteoporosis-related syndromes. Our findings indicate that Tonifying Shen-Yin and-Yang principles not only share some similarity but also obtain some difference in treating osteoporosis.

关键词： Osteoporosis Shen-Yin and-Yang Deficiency Tonifying Shen-Yin and-Yang Osteoclast Osteoblast