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Chinese Journal of.Polymer Science 2007年第5期25卷 519-523页

作者： N.C. Daf.der M.E. Haque f. akhtar Nuclear and Radiation Chemistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

Natural rubber latex （NRL） and methyl methacrylate （MMA） graf.ed rubber latex were blended in dif.erent ratios and irradiated at various absorbed doses by gamma rays f.om Co-60 source at room temperature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of.8 kGy. Modulus increases f.om 6.99 MPa to 9.87 MPa f.r an increase in proportion of.MMA graf.ed rubber f.om 40% to 60% in the blend at similar absorbed dose. Elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA graf.ed rubber content in the blends. The decreasing trend of.permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost f.at.

关键词： Natural rubber latex MMA graf.ed rubber latex Blend rubber Irradiation Cross-link.

OPTIMIZATION Of.THE SYNTHESIS Of.ACRYLAMIDE HYDROGEL BY γ-RAY IRRADIATION

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Chinese Journal of.Polymer Science 2004年第3期22卷 253-258页

作者： M.A. Chowdhury M.M. Alam M.f. Mina f. akhtar S.E. Kabir Department of.Chemistry Faculty of Science Jahangir Nagar University Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh Department of Chemistry Faculty of Science Jahangir Nagar University Dhaka Bangladesh

Hydrogels have been synthesized f.om 10%, 20%, 30%, 40%, 50% and 60% aqueous solutions of.acrylamide monomer by gamma radiation employing doses in the range of.0.2-30 kGy f.om a Co-60 source. The ef.ect of.solution concentration, γ-ray dose, pH and time was studied in order to observe the optimizing conditions in the characterization of.hydrogels. Gel f.action increases with dose f.r all concentrations indicating hundred-percentage conversion of.gel at doses 5 kGy f.r homogenous solutions in the range of.20%-50% concentration. On the other hand, 10% solution provides conversion less than 86% even at 30 kGy, whereas 60% monomer makes an inhomogeneous solution which stile gives about 100% gel f.action. Swelling of.hydrogels under water with respect to time varies with both the doses and concentrations due to the change of.crosslinking density in the gels. The maximum volume change of.hydrogels during swelling and water desorption mainly occurs within 24 h. Swelling is also enhanced with the rise of.pH due to change of.ionic content of.the solvent. Considering the amount of.gel f.action and the properties of.hydrogel, the samples prepared f.om 20% solution at 5 kGy show better results. Moreover, the ef.ect of.bacteria on hydrogel was f.und to be nil, suggesting a prohibition of.growth of.microorganism in it.

关键词： Hydrogel Acrylamide γ-radiation Swelling Microorganism

Acute Kidney Injury with Rhabdomyolysis: 25 Years Experience f.om a Tertiary Care Center

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Open Journal of.Nephrology 2015年第3期5卷 67-74页

作者： Rubina Naqvi f. akhtar E. Ahmed A. Naqvi A. Rizvi Sindh Institute of.Urology and Transplantation (SIUT) Karachi Pakistan

Objective: To describe patients presenting with acute kidney injury af.er rhabdomyolysis at a tertiary renal care center in Pakistan. Patients and Methods: An observational cohort of.patients identif.ed as having acute kidney injury (AKI) with rhabdomyolysis, which was diagnosed by rise in creatinine phosphokinase (CK) and lactate dehydrogenase (LDH) more than 4 times the ref.rence range whereas AKI was def.ned according to RIf.E criteria. On ultrasonography, all patients had normal size non obstructed kidneys, and no other co morbid. Results: Between January1990 to December 2014, 334 patients with rhabdomyolysis and AKI registered to this hospital. Mean age was 28.22 ± 11.22 years with M:f.ratio of.3.33:1. Mean values of.CK and LDH were 597,749.790 ± 180,461.360 and 4077.026 ± 5050.704 U/L with ref.rence range of.26 - 174 U/L and 91 - 180 U/L respectively. We divided the study population into 4 groups over timeline. Rhabdomyolysis etiology was divided in 3 groups;1) traumatic, 2) non-traumatic exertional, and 3) non-traumatic non-exertional. In the last group, which spans f.om 2010-2014, we treated many cases with toxic rhabdomyolysis and main toxin was paraphenylenediamine (PPD). The other causes showed more or less same prevalence over two and a half.decade, except non-traymatic exertional which has decreased during last 5 years without any explainable cause. Renal replacement therapy (RRT) was required on arrival in 94% cases. Complete renal recovery was observed in 70%, while 15.86% died and 10% were lost during recovery phase. A small number 2.69% lef. against medical advice during acute phase of.illness and 0.8% developed chronic kidney disease (CKD). Conclusion: The common clinical conditions f.und associated with rhabdomyolysis and AKI includes trauma, immobilization, sepsis, overexertion, and drugs and toxins. In recent years, we have seen many young patients with PPD poisoning;we have f.und good renal recovery in patients who survived initial 2 - 3 weeks.

关键词： Acute Kidney Injury Rhabdomyolysis RIf.E Criteria Torture Toxins PPD

Energy Meteorology f.r the Evaluation of.Solar f.rm Thermal Impacts on Desert Habitats

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ADVANCES IN ATMOSPHERIC SCIENCES 2025年第2期42卷 313-326页

作者： Coimbra, Carlos f. M. Univ Calif.San Diego Ctr Excellence Renewable Resource Integrat Jacobs Sch Engn Dept Mech & Aerosp Engn La Jolla CA 92093 USA Univ Calif.San Diego Ctr Energy Res La Jolla CA 92093 USA

This work addresses challenges and opportunities in the evaluation of.solar power plant impacts, with a particular f.cus on thermal ef.ects of.solar plants on the environment and vice-versa. Large-scale solar power plants are of.en sited in arid or desert habitats, which tend to include f.una and f.ora that are highly sensitive to changes in temperature and humidity. Our understanding of.both shortwave (solar) and longwave (terrestrial) radiation processes in solar power plants is complete enough to render the modeling of.radiation f.uxes with high conf.dence f.r most applications. In contrast to radiation, the convective environment in large-scale solar power plants is much more dif.icult to characterize. Wind direction, wind speed, turbulence intensity, dust concentration, ground condition, panel conf.guration density, orientation and distribution throughout the solar f.eld, all af.ect the local environment, the balance between radiation and convection, and in turn, the perf.rmance and thermal impact of.solar power plants. Because the temperatures of.the two sides of.photovoltaic (PV) panels depend on detailed convection-radiation balances, the uncertainty associated with convection af.ects the heat and mass transf.r balances as well. Those balances are critically important in estimating the thermal impact of.large-scale solar f.rms on local habitats. Here we discuss outstanding issues related with these transf.r processes f.r utility-scale solar generation and highlight potential pathways to gain usef.l knowledge about the convective environment directly f.om solar f.rms under operating conditions. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)

关键词： environmental impact solar f.rms thermal balances shortwave and longwave radiation convection (sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)

Rapid post-earthquake saf.ty assessment of.low-rise reinf.rced concrete structures

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 101-112页

作者： Koji Tsuchimoto Yasutaka Narazaki Billie f.Spencer,Jr. International Design Division Design DepartmentTaisei CorporationTokyo 163-0606Japan Zhejiang University–University of.Illinois Urbana-Champaign Institute Zhejiang UniversityHaining 314400China Civil and Environmental Engineering University of Illinois Urbana-ChampaignUrbana 61821USA

Many countries throughout the world have experienced large earthquakes,which cause building damage or *** such earthquakes,structures must be inspected rapidly to judge whether they are saf. to *** f.cilitate the inspection process,the authors previously developed a rapid building saf.ty assessment system using sparse acceleration measurements f.r steel f.amed *** proposed system modeled nonlinearity in the measurement data using a calibrated simplif.ed lumped-mass model and convolutional neural networks(CNNs),based on which the buildinglevel damage index was estimated rapidly af.er *** proposed system was validated f.r a nonlinear 3D numerical model of.a f.ve-story steel building,and later f.r a large-scale specimen of.an 18-story building in Japan tested on the E-Def.nse shaking ***,the applicability of.the saf.ty assessment system f.r reinf.rced concrete(RC)structures with complex hysteretic material nonlinearity has yet to be explored;the previous approach based on a simplif.ed lumpedmass model with a Bouc-Wen hysteretic model does not accurately represent the inherent nonlinear behavior and resulting damage states of.RC *** study extends the rapid building saf.ty assessment system to low-rise RC moment resisting f.ame structures representing typical residential apartments in ***,a saf.ty classif.cation f.r RC structures based on a damage index consistent with the current state of.practice is ***,a 3D nonlinear numerical model of.a two-story moment f.ame structure is created.A simplif.ed lumped-mass nonlinear model is developed and calibrated using the 3D model,incorporating the Takeda degradation model f.r the RC material *** model is used to simulate the seismic response and associated damage sensitive f.atures(DSf.f.r random ground *** resulting database of.responses is used to train a convolutional neural network(CNN)that perf.rms rapid saf.ty ***

关键词： rapid post-earthquake saf.ty assessment acceleration interstory drif. angle damage sensitive f.ature convolutional neural network RC structure simplif.ed non-linear analysis model Takeda degradation model

Relativistic hyperpolarizabilities of.atomic H, Li, and Be⁺ systems

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CHINESE PHYSICS B 2025年第2期34卷 230-239页

作者： Lu, Shan-Shan Zheng, Hong-Yuan Yan, Zong-Chao Babb, James f. Tang, Li-Yan Chinese Acad Sci Wuhan Inst Phys & Math Innovat Acad Precis Measurement Sci & Technol State Key Lab Magnet Resonance & Atom & Mol Phys Wuhan 430071 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Univ New Brunswick Dept Phys Fredericton NB E3B 5A3 Canada Ctr Astrophys Harvard & Smithsonian ITAMP 60 Garden St Cambridge MA 02138 USA

f.r atoms in external electric f.elds, the hyperpolarizabilities are the coef.icients describing the nonlinear interactions contributing to the induced energies at the f.urth power of.the applied electric f.elds. Accurate evaluations of.these coef.icients f.r various systems are crucial f.r improving precision in advanced atom-based optical lattice clocks and f.r estimating f.eld-induced ef.ects in atoms f.r quantum inf.rmation applications. However, there is a notable scarcity of.research on atomic hyperpolarizabilities, especially in the relativistic realm. Our work addresses this gap by establishing a novel set of.alternative f.rmulas f.r the hyperpolarizability based on the f.urth-order perturbation theory. These f.rmulas of.er a more reasonable regrouping of.scalar and tensor components compared to previous f.rmulas, thereby enhancing their correctness and applicability. To validate our f.rmulas, we perf.rm the calculations f.r the ground and low-lying excited pure states of.f.w-electron atoms H, Li, and Be+. The highly accurate results obtained f.r the H atom could serve as benchmarks f.r f.rther development of.other theoretical methods.

关键词： hyperpolarizabilities Stark ef.ect f.urth-order perturbation f.w-electron atoms 32.60.+i 32.10.Dk 31.15.xp 31.15.ac

Ef.ECT Of.GAMMA RAYS IN THE PREPARATION Of.POLYMER AND HYDROGEL f.OM ACRYLAMIDE MONOMER

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Chinese Journal of.Polymer Science 2003年第4期21卷 437-442页

作者： M.M.Alam M.f.Mina f.akhtar NRCD INST AERE GPO Box-3787 Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh

The f.rmation of.polymer and hydrogel f.om aqueous solutions having 20, 30 and 40% concentrations of.crylamide monomer by γ-ray irradiation processing in the dose range 0.06-30 kGy using a Co-60 source and theircharacterization have been observed. Polymer conversion and gel f.action are f.und to depend on radiation doses. Polymerconversion increases with the increase of.dose, depending on the solution concentration, where maximum conversion isachieved at 0.18, 0.16 and 0.10 kGy f.r 20%, 30% and 40% concentrations, respectively. On the other hand, gel f.actionincreases with dose f.om the gel point (0.12 kGy) f.r all concentrations, where 100% conversion of.gel occurs at doses≥5 kGy. Tensile strength, viscosity and molecular weight (M_w) of.polymer samples increase with both the dose and theconcentration, showing a high value of.M_w up to≈10~8. Swelling of.hydrogels under water with respect to time varies due tothe variation of.cross-linking density f.rmed in the gels and the maximum swelling mainly occurs within 24 h. A remarkable change of.surf.ce morphology reveals characteristic f.atures of.monomer, polymer and hydrogel f.lms.

关键词： Polymer Hydrogel γ-Radiation Cross-linking Swelling

Magnitude, spatial patterns and drivers of.methane f.uxes f.om coastal salt marshes and mangrove f.rests in China

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Science China Earth Sciences 2025年第3期68卷 850-866页

作者： Yixuan YU Derrick Y.f.LAI Minjie HU Chuan TONG Key Laboratory of.Humid Subtropical Eco-geographical Process of.Ministry of.Education Fujian Normal University School of.Geographical Sciences Fujian Normal University Department of.Geography and Resource Management The Chinese University of Hong Kong

Methane（CH4） is a highly potent greenhouse gas due to its high radiative f.rcing and global warming *** the magnitude, spatial patterns, and drivers of.CH4emission f.om wetlands at the regional scale is crucial f.r f.rmulating suitable strategies to mitigate f.ture climate change. In this study, we synthesized the CH4f.ux data reported f.r major plant communities in the coastal salt marshes and mangrove f.rests in China and produced a spatial map of.CH4f.uxes f.om the mangrove sediments and salt marshes in China based on the results of.machine learning models. Moreover, we examined the main drivers of.CH4f.ux f.om these coastal wetlands and estimated the annual CH4emissions f.om the salt marshes and mangrove f.rests in dif.erent coastal provinces of.China using a bottom-up approach. Our results showed that the mean CH4f.uxes f.om the salt marsh and mangrove ecosystems in China were 2.22±0.29 and 2.26±0.55 mg m-2h-1, respectively. Across China, the total annual CH4emission f.om salt marshes was 31,179.75 Mg CH4a-1, while that f.om mangroves was 5,533.97 Mg CH4a-1with the sediments contributing to 12.7%(701.64 Mg CH4a-1) of.the total ef.lux. The salt marshes and mangroves in China accounted f.r 2.75% and 0.14%–0.15% of.the global annual CH4emissions f.om these two ecosystems,respectively. Moreover, we f.und that CH4emissions f.om the salt marshes and mangroves could of.set the cooling impact arising f.om net carbon dioxide uptake by 88% and 53%, respectively, over a 100-year time scale. Mean annual temperature, soil moisture, and soil organic carbon content were the main f.ctors controlling CH4emissions f.om these coastal ***, we f.und that CH4f.uxes f.om the salt marshes in China decreased with latitude, which implied a possible increase in marsh CH4emission in response to global warming that should be considered caref.lly when developing nature-based climate solutions to achieve national goals f.r carbon neutrality.

关键词： Salt marsh Mangrove Methane f.ux Spatial pattern Driving f.ctors China

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Energy Meteorology f.r the Evaluation of.Solar f.rm Thermal Impacts on Desert Habitats

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Advances in Atmospheric Sciences 2025年第02期 313-326页

作者： Carlos f.M.COIMBRA Department of.Mechanical and Aerospace Engineering Jacobs School of Engineering Center of Excellence in Renewable Resource Integration and Center for Energy Research University of California San Diego

This work addresses challenges and opportunities in the evaluation of.solar power plant impacts, with a particular f.cus on thermal ef.ects of.solar plants on the environment and vice-versa. Large-scale solar power plants are of.en sited in arid or desert habitats, which tend to include f.una and f.ora that are highly sensitive to changes in temperature and humidity. Our understanding of.both shortwave(solar) and longwave(terrestrial) radiation processes in solar power plants is complete enough to render the modeling of.radiation f.uxes with high conf.dence f.r most applications. In contrast to radiation, the convective environment in large-scale solar power plants is much more dif.icult to characterize. Wind direction, wind speed, turbulence intensity, dust concentration, ground condition, panel conf.guration density, orientation and distribution throughout the solar f.eld, all af.ect the local environment, the balance between radiation and convection,and in turn, the perf.rmance and thermal impact of.solar power plants. Because the temperatures of.the two sides of.photovoltaic(PV) panels depend on detailed convection–radiation balances, the uncertainty associated with convection af.ects the heat and mass transf.r balances as well. Those balances are critically important in estimating the thermal impact of.large-scale solar f.rms on local habitats. Here we discuss outstanding issues related with these transf.r processes f.r utility-scale solar generation and highlight potential pathways to gain usef.l knowledge about the convective environment directly f.om solar f.rms under operating conditions.

关键词：

VARIATION Of.PHYSICO-CHEMICAL PROPERTIES Of.RADIATION CROSSLINKED RUBBER WITH STORAGE TIME

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Chinese Journal of.Polymer Science 2005年第5期23卷 497-501页

作者： N.C.Daf.der M.E.Haque f.akhtar Nuclear and Radiation Chemistry Division

The ef.ect of.storage on physico-chemical properties of.non-irradiated natural rubber and radiation vulcanized natural rubber （RVNR） were evaluated. The rubber f.lms were stored under two dif.erent conditions, namely in open air and sealed polyethylene bags. The antioxidant, tris（nonylated phenyl） phosphite （TNPP） was used f.r preventing degradation of.RVNR f.lms. Gel content, cross-link density, tensile strength at break and 500% elongation of.rubber f.lms were measured. The results show that the retention （%） of.tensile properties of.rubber f.lms with TNPP is higher than that of.rubber f.lms without antioxidants. The rubber f.lms stored in polyethylene bags also show better retention of.tensile properties than those of.rubber f.lms stored in open air.

关键词： Storage Radiation Tensile Properties Antioxidant.