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Comparison of paleoclimatic characteristics between monsoon and westerly areas,China

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Chinese Science Bulletin 2001年第S1期46卷 119-124页

作者： Wei Ye fang ji Zhejiang Normal Univ Coll Life & Environm Sci Jinhua 321004 Peoples R China

For past decades there have been many studies on the climate features during the last interglacial and glacial periods. A comparison between the loess record of western China with that of monsoon areas shows some regional differences. ( i) Generally, the climate of the Yili region since the late Pleistocene was dry, with fluctuations. Late Pleistocene climate change in the study area can be divided into 5 stages, corresponding to 5 marine isotopic stages (MIS 1-MISS), (ii) Evidence from grain size composition, magnetic susceptibility, carbonate content, pollen assemblage and geochemistry shows that the climate during the last glacial period was instable. During MIS4 the westerly winds were strong and the humidity was relatively high. Compared with the early stage, MIS2 was dry. In MIS3, westerly winds were relatively weak; pedogenesis prevailed, forming paleo-sols. (iii) In contrast to the Loess Plateau the deposition rate of dust at the early stage was higher than at the late stage of the last galical

关键词： paleoclimatic characteristics monsoon area western China.

Control of Titanium Alloy Thin Plate Welding Distortion by Trailing Peening

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Journal of Materials Science & Technology 2003年第z1期19卷 184-186页

作者： Xuesong LIU Hongyuan fang Shude ji Zhibo DONG State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China

The technology of trailing peening is a kind of promisingly bran-new technology which can be used to control weldingstress and distortion of Ti alloy thin plate. Control of TC4 Ti alloy thn plate welding stress and distortion underthe condition of conventional welding and trailing peening is performed, respectively. The results show that thetechnology of trailing peening effectively reduces deflection and transverse shrinkage of thin plate weldment. Themaximum deflection is decreased from 15 mm under the conditior of conventional welding to 5 mm, while the weldtransverse shrinkage is decreased from 0.5 mm to about 0.1 mm.

关键词： Control of residual stress and distortion, Trailing peening, TC4 Ti alloy

Effects of light intensity and photoperiod on runner plant propagation of hydroponic strawberry transplants under LED lighting

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International Journal of Agricultural and Biological Engineering 2019年第6期12卷 26-31页

作者： jianfeng Zheng Dongxian He fang ji Key Laboratory of Agricultural Engineering in Structure and Environment of Ministry of Agriculture and Rural Affairs College of Water Resources and Civil EngineeringChina Agricultural UniversityBeijing 100083China

Vegetative propagation of strawberry(Fragaria×ananassa Duch.)in the plant factory with artificial lighting is considered as an effective approach to produce high-quality *** this study,mother plants of‘Benihoppe’strawberry were grown hydroponically for 50 d under eight LED lighting treatments by combining four levels of light intensity(200,250,300 and 350mmol/(m^(2)·s))and two photoperiods(12 h/d and 16 h/d).Runner development,growth of runner plants,photon yield and energy yield in runners and runner plants were investigated to evaluate the strawberry propagation *** indicated that length of runners decreased linearly with increasing daily light integral(DLI)under each photoperiod and was significantly shorter under photoperiod of 16 h/*** elongation was inhibited by high *** of runners and runner plants formed by mother plants increased by 38.9%and 33.7%,when DLI increased from 8.6 to 11.5 mol/(m^(2)·d),respectively;however,no further increase was observed when DLI was higher than 11.5 mol/(m^(2)·d).Similar trends were found in crown diameter and biomass of primary and secondary runner *** impact of high DLI(20.2 mol/(m^(2)·d))on photosynthetic capacity of runner plants was observed as a decrease in leaf net photosynthetic rate,potential maximum photochemical efficiency of PSII,and chlorophyll ***,photon yield and energy yield in runners and runner plants decreased significantly with increasing ***,DLI in a range of 11.5-17.3 mol/(m^(2)·d)is beneficial to improve strawberry propagation efficiency and quality of runner plants,and 11.5 mol/(m^(2)·d)is optimal for the strawberry propagation of runner plants in the LED plant factory because of the higher photon and energy yields.

关键词： hydroponic strawberry vegetative propagation daily light integral photon yield

Life cycle assessment of pyrolysis process of Desmodesmus sp.

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International Journal of Agricultural and Biological Engineering 2015年第5期8卷 105-112页

作者： Li Gang ji fang Zhou Yuguang Dong Renjie College of Engineering/Biomass Engineering Center China Agricultural UniversityBeijing 100083China Key Laboratory of Clean Production and Utilization of Renewable Energy Ministry of AgricultureBeijing 100083China Chinese Academy of Agricultural Engineering Beijing 100125China

This paper described a comprehensive assessment of the pyrolysis process of 1 kg Desmodesmus *** in BG11 medium at the optimum temperature by using life cycle assessment *** assessment took 1 kg of Desmodesmus *** a functional unit,and chose energy efficiency analysis and potential environmental impact as assessment *** results showed that the energy conversion efficiency index of the pyrolysis process was above 1,which meant the pyrolysis process was *** primary impact of the pyrolysis process on the environment was eutrophication;which followed by photochemical ozone synthesis and acidification;and global warming impact was the *** overall environmental impact during the whole life cycle was 1347.63 mPET2000.

关键词： life cycle assessment(LCA) microalgae pyrolysis energy conversion efficiency environmental impact

Establishment and evaluation of a risk prediction model for gestational diabetes mellitus

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World Journal of Diabetes 2023年第10期14卷 1541-1550页

作者： Qing Lin Zhuan-ji fang Department of Obstetrics Fujian Maternity and Child Health HospitalCollege of Clinical Medicine for Obstetrics and Gynecology and PediatricsFujian Medical UniversityFuzhou 350001Fujian ProvinceChina

BACKGROUND Gestational diabetes mellitus(GDM)is a condition characterized by high blood sugar levels during *** prevalence of GDM is on the rise globally,and this trend is particularly evident in China,which has emerged as a significant issue impacting the well-being of expectant mothers and their *** and addressing GDM in a timely manner is crucial for maintaining the health of both expectant mothers and their developing ***,this study aims to establish a risk prediction model for GDM and explore the effects of serum ferritin,blood glucose,and body mass index(BMI)on the occurrence of *** To develop a risk prediction model to analyze factors leading to GDM,and evaluate its efficiency for early *** The clinical data of 406 pregnant women who underwent routine prenatal examination in Fujian Maternity and Child Health Hospital from April 2020 to December 2022 were retrospectively *** to whether GDM occurred,they were divided into two groups to analyze the related factors affecting ***,according to the weight of the relevant risk factors,the training set and the verification set were divided at a ratio of 7:***,a risk prediction model was established using logistic regression and random forest models,and the model was evaluated and *** Pre-pregnancy BMI,previous history of GDM or macrosomia,hypertension,hemoglobin(Hb)level,triglyceride level,family history of diabetes,serum ferritin,and fasting blood glucose levels during early pregnancy were *** factors were found to have a significant impact on the development of GDM(P<0.05).According to the nomogram model’s prediction of GDM in pregnancy,the area under the curve(AUC)was determined to be 0.883[95%confidence interval(CI):0.846-0.921],and the sensitivity and specificity were 74.1%and 87.6%,*** top five variables in the random forest model for predicting the occurrence of GDM were serum ferriti

关键词： Gestational diabetes mellitus Prediction model Model evaluation Random forest model Nomograms Risk factor

Effects of LED light quality on the growth of pepper seedling in plant factory

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International Journal of Agricultural and Biological Engineering 2019年第5期12卷 44-50页

作者： Nan Liu fang ji Lijun Xu Dongxian He Key Lab.Agricultural Engineering in Structure and Environment of Ministry of Agriculture and Rural Affairs College of Water Resources&Civil EngineeringChina Agricultural UniversityBeijing 100083China

The extensive environment,especially low temperature and weak lighting in winter and spring,which limits the growth of pepper(Capicum annuum L.)seedlings,the use of plant factory with artificial lighting technology can effectively control the lighting environment to produce high-quality *** this study,white LED lamps with R:B ratio of 0.7(L0.7)and 1.5(L1.5)and red-blue LED lamps with R:B ratio of 3.5(L3.5)were used to cultivate seedlings of“CAU-24”pepper in the light intensity of 250μmol/m^(2)·s and photoperiod of 12 h/d,white fluorescent lamps with R:B ratio of 1.7(F1.7)was used as *** results showed that plant height,stem diameter,hypocotyl length,biomass accumulation,light energy use efficiency(LUE)and electric energy use efficiency(EUE)of pepper seedling under L1.5 were the *** 36 days of sowing,the dry weight of shoot reached 302.8±45.2 mg/*** area reached maximum value of 153.5±22.0 cm^(2) under *** contents of chlorophyll a,chlorophyll b and total chlorophyll of pepper seedling leaves under all kinds of LED light were greater than F1.7,but there was no significant difference in net photosynthetic *** total dry weight with lamp electric power consumption of L1.5 were 3.0 g/(kW·h)which was 1.5,2,and 3 times greater than that of L3.5,L0.7,and F1.7,***,compared with fluorescent lamp and other LED lamps,the white LED light quality with R:B ratio of 1.5 is suitable for pepper seedling production in plant factory because of the high LED lighting efficiency,greater LUE and EUE.

关键词： pepper seedlings LED light quality R:B ratio light energy use efficiency(LUE) electric energy use efficiency(EUE)

Effects of plug tray cell size on the growth of Atractylodes Chinensis (DC) Koidz seedlings

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 45-52页

作者： Kaixuan Shi Juwen Liang fang ji Dongxian He Key Laboratory of Agricultural Engineering in Structure and Environment of MARA College of Water Resources&Civil EngineeringChina Agricultural UniversityBeijing 100083China

Atractylodes Chinensis(DC)Koidz is a perennial herb often used as a prescription medicine for influenza,to invigorate the spleen and remove *** quality of the herb is determined by the quality of the *** traditional *** seedling production technique has nonuniform seedlings and low *** plug seedling technique was used to produce *** *** study was conducted to determine the growth characteristics of *** seedlings according to the cell size of plug trays and number of days after *** height,stem diameter,rhizome diameter,number of leaves,leaf area,and shoot dry and fresh weight of *** seedlings were significantly higher in the P32-D treatment than in the P72,P50,and P32 treatments,but not significantly different from the P28-D treatment 60 d after *** P28-D treatment resulted in a considerable drop in rhizome fresh weight and healthy seedling index,both of which are key indicators for assessing seedling *** the differences in Pn among treatments were not significantly different,Tr was considerably greater in *** seedlings treated with P32-D and P28-D than in the other three *** P32-D and P28-D treatments had considerably greater potential maximum photochemical efficiency of PSII,quantum yield of photosystem II,photochemical quenching and electron transport rate than the other three *** vitality of *** seedlings was significantly stronger in the P32-D treatment than in the other four treatments,and it was 1.9 times higher than in the P28-D *** soluble protein,soluble sugar,and starch contents of *** seedlings were highest in the P32-D treatment,but the differences among treatments were not ***,EUE,PY and EY were significantly higher in the P32-D treatment than in the other four treatments,being 1.3,1.3,1.4 and 1.4 times higher than in P28-D,*** the other hand,as for the change in the gro

关键词： Atractylodes Chinensis(DC)Koidz plug seedling plug tray cell size

Optimal red:blue ratio of full spectrum LEDs for hydroponic pakchoi cultivation in plant factory

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 72-77页

作者： Yunong Li Nan Liu fang ji Dongxian He Key Lab.Agricultural Engineering in Structure and Environment of Ministry of Agriculture and Rural Affairs College of Water Resources and Civil EngineeringChina Agricultural UniversityBeijing 100083China Big Herdsman Machinery Co. LtdQingdao 266108ShandongChina

Pakchoi,a popular leafy vegetable in China,is expected to be planted in plant factories with artificial lighting(PFALs).In order to examine the effects of different red and blue light ratios(R:B ratio)on growth,photosynthesis,and absorption spectrum of plant leaves,and to analyze the energy use efficiency,the pakchoi(Brassica Chinensis ***)was cultivated hydroponically under white LEDs with R:B ratios of 0.9(L0.9)and 1.8(L1.8),white plus red LEDs with R:B ratios of 2.7(L2.7)and 4.0(L4.0)for 40 d,*** results showed that the leaf length and width were significantly greater in the L0.9 treatment than in other treatments,and the dry weight per plant increased by over 33%when R:B ratio decreased from 4.0 to *** net photosynthesis rates of pakchoi leaves ranged from 9.2 to 9.6μmol/(m2·s)under different lighting conditions,which had no significant *** biggest difference in the spectrum absorptance of pakchoi leaves was expressed in green light waveband,and the highest absorption of plant leaves was under L0.9 and L1.8 *** light energy use efficiency(LUE),photon yield(PY),and energy yield(EY)in L0.9 were over 25%higher than that in the other treatments,while there was no significant difference in the electrical energy use efficiency(EUE).In conclusion,an optimal light quality to cultivate pakchoi in PFALs was the white LEDs with R:B ratio of 0.9,and this finding could provide a promising lighting environment to hydroponic pakchoi yield and energy use efficiency.

关键词： pakchoi R:B ratio yield absorption spectrum energy use efficiency

Isolation of microalgae with growth restriction and nutrient removal from alkaline wastewater

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International Journal of Agricultural and Biological Engineering 2015年第6期8卷 62-68页

作者： ji fang Wang Yingkuan Li Gang Zhou Yuguang Dong Renjie College of Engineering/Biomass Engineering Center China Agricultural UniversityBeijing 100083China Key Laboratory of Clean Production and Utilization of Renewable Energy Ministry of AgricultureP.R.ChinaBeijing 100083China Chinese Academy of Agricultural Engineering Beijing 100125China

In order to isolate a well-tolerated microalgae strain and study its capability of wastewater treatment,a newly microalgae strain was isolated and identified from fresh *** phylogenetic analysis indicates that this strain has a close relationship with Desmodesmus sp.,named as EJ *** effects of temperature,pH value and NaCl concentration on growth of Desmondesmus *** investigated;the capability of nutrient removal from alkaline wastewater was also *** *** 9-2 had a wide pH adaptation range(3-12)and could remove nitrogen,phosphorus and COD which might substantially decrease the cost of biofuel *** research can provide evidence for outdoor large-scale cultivation of microalgae.

关键词： microalgae isolation growth restriction alkaline wastewater nutrient removal algae-based fuel wastewater treatment