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Petroleum Science 2021年第2期18卷 479-494页

作者： Dao-Yi Zhu Xing-Yu Fang Ren-xian Sun zeng-Hao Xu Yang Liu Ji-Yang Liu College of Petroleum China University of Petroleum-Beijing at KaramayKaramay834000XinjiangChina

Temporary plugging agent(TPA)is widely used in many fields of petroleum reservoir drilling and production,such as temporary plugging while drilling and petroleum well stimulation by diverting in acidizing or fracturing *** commonly used TPA mainly includes hard particles,fibers,gels,and composite ***,current particles have many limitations in applications,such as insufficient plugging strength and slow degradation *** this paper,a degradable pre-formed particle gel(DPPG)was *** results show that the DPPG has an excellent static swelling effect and self-degradation *** a decrease in the concentration of total monomers or cross-linker,the swelling volume of the synthesized DPPG gradually ***,the entire self-degradation time gradually *** increase in 2-acrylamide-2-methylpropanesulfonic acid(AMPS)in the DPPG composition can significantly increase its swelling ratio and shorten the self-degradation ***,DPPG has excellent high-temperature resistance(150°C)and high-salinity resistance(200,000 mg/L NaCl).Core displacement results show that the DPPG has a perfect plugging effect in the porous media(the plugging pressure gradient was as high as 21.12 MPa),and the damage to the formation after degradation is incredibly ***,the DPPG can be used as an up-and-coming TPA in oil fields.

关键词： Temporary plugging agents Pre-formed particle gel(PPG) Degradable PPG Petroleum drilling Petroleum production

Tumor targeting of HPMA copolymer conjugates containing sulfadiazine groups

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Chinese Chemical Letters 2012年第7期23卷 875-878页

作者： Jian Chao Yuan Xiao Li Xie xian Wu zeng Hong Yun Guo Cheng Ping Miao Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education Key Laboratory of Polymer Materials of Gansu ProvinceCollege of Chemistry&Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China Department of Nuclear Medicine Gansu Academy of Medical Sciences&Gansu Provincial Tumor HospitalLanzhou 730050China

To develop new tumor targeting macromolecular conjugates,poly（HPMA）-SD-APMA-DTPA（HPMA：N-（2-hydroxypropyl）- methacrylamide;APMA：N-（3-ammopropyl）methacrylamide;DTPA：diethylenetriaminepentaacetic acid;SD：sulfadiazine） was synthesized and *** poly（HPMA）-SD-DTPA conjugates were radiolabeled with the radionuclide ^（99m）Tc and tested for uptake by cultured H22 cells in ***-^（99m）Tc（radiotracer 1） and poly（HPMA）-DTPA-^（99m）Tc（radiotracer 2） were also synthesized and characterized for *** uptake of poly（HPMA）-SD-DTPA-^（99m）Tc（radiotracer 3,34.76%） was significantly higher than that of poly（HPMA）-DTPA-^（99m）Tc（16.40%）,indicating that uptake of the poly（HPMA）-SD-DTPA-^（99m）T was active *** uptake of poly（HPMA）-DTPA-^（99m）Tc was significantly higher than that of DTPA-^（99m）Tc（2.98%）, suggesting that uptake of the poly（HPMA）-DTPA-^（99m）T was passive *** data suggest that the poly（HPMA）-SDAPMA -DTPA conjugates might be useful as tumor targeting macromolecular conjugates.

关键词： Tumor targeting HepatoceUular carcinoma HPMA copolymer conjugates Radiotracer

Sensitizing photoactive metal-organic frameworks via chromophore for significantly boosting photosynthesis

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Chinese Chemical Letters 2024年第5期35卷 519-522页

作者： Lihua Ma Song Guo Zhi-Ming Zhang Jin-Zhong Wang Tong-Bu Lu xian-Shun zeng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Institute for New Energy Materials and Low Carbon Technologies School of Material Science&EngineeringTianjin University of TechnologyTianjin 300384China

Photosensitization related to energy/electron transfer process is of great importance to natural ***,we proposed a promising strategy to improve the sensitizing ability of the typical photoactive MOFs(UiO-Ir)by engineering its metal coordination center with NBI(1,8-naphthalenebenzimidizole)*** resulting MOFs(UiO-Ir-NBI)exhibited a strong sensitizing ability for significantly boosting ***,the catalytic yield of 2-chloroethyl ethyl sulfoxide with UiO-Ir-NBI can reach 99%,over 6 times higher than that with UiO-Ir(16.4%).Moreover,UiO-Ir-NBI exhibited an excellent catalytic stability and a broad substrate tolerance,highlighting its great application *** investigations revealed that the strong visible light absorption,long excited state lifetime and efficient electron-hole separation of UiO-Ir-NBI greatly contributed to harvesting visible light and facilitating interface electron/energy transfer for efficient solar energy *** work provides a new horizon to boost photosythesis of MOFs by engineering their metal sensitizing centers at a molecular level.

关键词： Metal-organic framework Photocatalysis Excited state Strong visible absorption Iridium complex

Medical Image Compression by Applying 3D DWT in PACS

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 313-318页

作者： Wang Si-xian Li Fei-peng zeng Fa-long Liao Meng-yang Li Hui Wuhan Univ Wuhan China

The process of image compression in a practical Picture Archiving and Communication System (PACS) was discussed with detail. To fully reduce the inter-slice correlation existing in the volumetric image sets generated by CT and MR, 3D Discrete Wavelet Transformation (DWT) was introduced in our application. Instead of using a fixed quantizer of lossless low frequency and distinct loss of high frequency, an adaptive quantizer was devised taking MSE as the performance index. In the low frequency subband, DPCM was replaced withS+P transform to facilitate coding computation. Compared with JPEG or 2D DWT, our method is 20%–50% more efficient. Furthermore, preliminary tests showed that 33 dB may be the maximal distortion threshold for CT images.

关键词： PACS 3D DWT S+P transformation optimal bit allocation maximal distortion threshold

Pre-heating temperature induced flowability and wax deposition characteristics of crude oil adding wax inhibitors

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Petroleum Science 2023年第4期20卷 2468-2478页

作者： Bo Yao Hao-Ran Zhu Bao-Dong Yan Chuan-xian Li Fei Yang Guang-Yu Sun Hong-Bo zeng College of Pipeline and Civil Engineering China University of PetroleumQingdaoShandong266580People's Republic of China Department of Chemical and Materials Engineering University of AlbertaEdmontonABT6G 1H9Canada School of Petroleum Engineering Changzhou UniversityChangzhouJiangsu213164People's Republic of China China Oil&Gas Pipeline Network Corporation Beijing100020China

This paper investigated the effects of pre-heating treatment temperatures(T_(pre))on the flowability and wax deposition characteristics of a typical waxy crude oil after adding wax *** is found that there is little difference in wax precipitation exothermic characteristics of crude oils at different T_(pre),as well as the wax crystal solubility coefficient in the temperature range of 25-30℃.For the undoped crude oil,the flowability after wax precipitation gets much improved and the wax deposition is alleviated as T_(pre)*** T_(pre)=50℃,the viscosity and wax deposition rate of crude oil adding wax inhibitors are higher than those of the undoped crude *** the T_(pre)increases to 60,70,and 80℃,the flowability of the doped crude oil are largely improved and the wax deposition is suppressed with the T_(pre)increase,but the wax content of wax deposit increases *** is speculated that,on the one hand,the T_(pre)increase helps the dispersion of asphaltenes into smaller sizes,which facilitates the co-crystallization with paraffin waxes and generates more aggregated wax crystal *** weakens the low-temperature gel structure and increases the solid concentration required for the crosslink to form the wax *** the other hand,the decrease in viscosity increases the diffusion rate of wax molecules and accelerates the aging of wax *** experimental results have important guiding significance for the pipeline transportation of doped crude oils.

关键词： Pre-heating treatment Wax inhibitor Flowability Wax deposition Waxy crude oil

Fast nuclide identification based on a sequential Bayesian method

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Nuclear Science and Techniques 2021年第12期32卷 116-127页

作者： Xiao-Zhe Li Qing-xian Zhang He-Yi Tan Zhi-Qiang Cheng Liang-Quan Ge Guo-Qiang zeng Wan-Chang Lai Chengdu University of Technology The College of Nuclear Technology and Automation EngineeringChengdu 610059China

The rapid identification of radioactive substances in public areas is ***,traditional nuclide identification methods only consider information regarding the full energy peaks of the gamma-ray spectrum and require long recording times,which lead to long response *** this paper,a novel identification method using the event mode sequence(EMS)information of target radionuclides is *** EMS of a target radionuclide and natural background radiation were established as two different probabilistic models and a decision function based on Bayesian inference and sequential testing was *** proposed detection scheme individually processes each *** a photon is detected and accepted,the corresponding posterior probability distribution parameters are estimated using Bayesian inference and the decision function is ***,value of the decision function is compared to preset detection thresholds to obtain a detection ***ments on different target radionuclides(137Cs and 60Co)were *** count rates of the regions of interest(ROI)in the backgrounds between[651,671],[1154,1186],and[1310,1350]keV were 2.35,5.14,and 0.57 CPS,*** experimental results demonstrate that the average detection time was 6.0 s for 60Co(with an activity of 80400 Bq)at a distance of 60 cm from the *** average detection time was 7 s for 137Cs(with an activity of 131000 Bq)at a distance of 90 cm from the *** results demonstrate that the proposed method can detect radioactive substances with low activity.

关键词： Natural radiation Nuclide identification Sequential testing Nuclear safety

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi Gu Mao-Lin Xiong Liang-Quan Ge Qing-xian Zhang Guo-Qiang zeng Heng Lu Sheng-Liang Guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

Design and field measurement of a dipole magnet for a newly developed superconducting proton cyclotron beamline

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Nuclear Science and Techniques 2018年第9期29卷 214-221页

作者： Jun-Sheng Zhang Jin-Xing Zheng Yun-Tao Song Wu-Quan Zhang Ming Li xian-Hu zeng Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230031China

The design, field quality optimization, multipole field analysis, and field measurement of a dipole for a newly developed superconducting proton cyclotron(SC200) beamline are presented in this paper. The maximum magnetic field of the dipole is 1.35 T; the bending radius is 1.6 m with a proton beam energy in the range of70–200 Me V. The magnetic field was calculated with 2 D and 3 D simulations, and measured with a Hall mapping system. The pole shim and end chamfer were optimized to improve the field quality. Based on the simulated results,the multipole field components in the good-field region were studied to evaluate the field quality. The results showed that the field quality is better than ± 5 × 10^(-4) at1.35 T with shimming and chamfering. For the transverse field homogeneity, the third-order(B3) and fifth-order(B5)components should be controlled with symmetrical *** second-order(B2) component was the main disturbance for the integral field homogeneity; it could be improved with an end chamfer. The magnet manufacturing and field measurement were performed in this project. The measurement results demonstrated that the magnetic design and field quality optimization of the 45° dipole magnet can achieve the desired high field quality and satisfy the physical requirements.

关键词： Magnet Field quality Pole shim End chamfer Multipole field component

Radical resection and outcome for malignant tumors of the pancreatic body and tail

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World Journal of Gastroenterology 2009年第42期15卷 5346-5351页

作者： Shao-Liang Han Wei-Jian Zhang Xiao-Feng Zheng xian Shen Qi-Qiang zeng Qing-Hong Ke Department of General Surgery the First Affiliated Hospital of Wenzhou Medical College Wenzhou 325000 Zhejiang Province China Department of Hepatobiliopancreatic Surgery the First Affiliated Hospital Zhejiang University Hangzhou 310009 Zhejiang Province China

AIM： TO analyze the factors influencing radical （R0） resection rate and surgical outcome for malignant tumor of the pancreatic body and tail. METHODS： The clinical and operative data and follow- up results of 214 pancreatic body and tail cancer patients were analyzed retrospectively. RESULTS： One hundred and twenty/214 pancreatic body and tail cancer patients underwent surgical treatment; the overall resection rate was 59.2% （71/120）, and the R0 resection rate was 40.8% （49/120）. Compared with non-R0 treatment, the patients receiving an R0 resection had smaller size tumor （P 〈 0.01）, cystadenocarcinoma （P 〈 0.01）, less lymph node metastasis （P 〈 0.01）, less peri-pancreatic organ involvement （P 〈 0.01） and earlier stage disease （P 〈 0.01）. The overall 1-, 3- and 5-year survival rates for pancreatic body and tail cancer patients were 12.7% （251197）, 7.6% （151197） and 2.5% （5/197）, respectively, and ductal adenocarcinoma patients had worse survival rates [15.0% （9/60）, 6.7% （4/60） and 1.7% （1/60）, respectively] than cystadenocarcinoma patients [53.8% （21139）, 28.2% （11139） and 10.3% （4139）] （P 〈 0.01）. Moreover, the 1-, 3- and 5-year overall survival rates in patients with RO resection were 55.3% （26/47）, 31.9% （15/47） and 10.6% （5/47）, respectively, significantly better than those in patients with palliative resection [9.5% （2/21）, 0 and 0] and in patients with bypass or laparotomy [1.2% （1/81）, 0 and 0] （P 〈 0.01）. CONCLUSION： Early diagnosis is crucial for increasing the radical resection rate, and radical resection plays an important role in improving survival for pancreatic body and tail cancer patients.

关键词： Pancreatic neoplasm Body and tail of pancreas Pancreatectomy Survival Cystadenocarcinoma

Verification of a self-developed CFD-based multi-physics coupled code MPC-LBE for LBE-cooled reactor

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Nuclear Science and Techniques 2021年第5期32卷 84-100页

作者： Zhi-Xing Gu Qing-xian Zhang Yi Gu Liang-Quan Ge Guo-Qiang zeng Mu-Hao Zhang Bao-Jie Nie College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

To perform an integral simulation of a pool-type reactor using CFD code,a multi-physics coupled code MPC-LBE for an LBE-cooled reactor was proposed by integrating a point kinetics model and a fuel pin heat transfer model into self-developed CFD *** code verification,a code-to-code comparison was employed to validate the CFD ***,a typical BT transient benchmark on the LBE-cooled XADS reactor was selected for verification in terms of the integral or system *** on the verification results,it was demonstrated that the MPC-LBE coupled code can perform thermal-hydraulics or safety analyses for analysis for processes involved in LBE-cooled pool-type reactors.

关键词： LBE-cooled pool-type reactor Computational fluid dynamics Multi-physics coupling code Safety analysis code Verification