Journal of Lanzhou University（Natural Sciences） 2002 Issue 4 Positive solutions of nonlinear second order boundary value problems for integro-differential equations

Positive solutions of nonlinear second order boundary value problems for integro-differential equations
li yong xiang ; zuo rui

..............page:1-6

Qualitative analysis of a class of predator-prey system exploited
fan yong hong ; quan hong shun

..............page:7-11

The pointwise converse results for Sz（a）sz-Durrmeyer operators
liu xi wu ; wang jian jun

..............page:12-16

Type 1 χ-continuous modules and type 1 χ-quasi-continuous modules
yang shi zhou

..............page:17-21

New verifiable encryptions and their applications
wang cai fen ; ge jian hua

..............page:22-27

Vibration and stability of corrugated core sandwich plates with all edges simply supported
wu zuo ; yu huan ran

..............page:28-32

Thermal post buckling of rods with variable cross sections
li shi rong ; zhou you he ; song zuo

..............page:33-38

Study of the tribological behaviors of iron based metal ceramic composites
shi zong li ; zhang guo qiang ; du xin kang ; li zhong zuo

..............page:39-43

The achievement of a high-speed counter timer
ma yong jie ; jia wen bao ; ma sheng qian

..............page:44-46

Preparation and characterization of porous alumina membrane
lu mei ; zuo dong huan ; li hu lin

..............page:47-54

Application probabilistic neural network to classify of the carcinogenicity of polycyclic aromatic hydrocarbons
xiang yu hong ; yao xiao jun ; zhang rui sheng ; liu man cang ; hu zhi de ; fan bo tao

..............page:55-60

Chemical constituents of the aerial parts of Carpesium cernuun
yang chao ; wang xing ; shi yan ping ; jia zhong jian

..............page:61-67

Semi-synthesis and antibacterial activity of 7β-(1-Aryl-5 methyl-1,2,3-triazol-4-amido)-3-(2-arylamino-1,3,4-thiadiazol-5-thiomethylene) cephalosporins
hui xin ping ; zhang yan ; wang qin ; xu peng fei ; zhang zi yi ; guan zuo wu

..............page:68-72

Effect of ultrasound on precipitation from super caustic aluminate solution of the bayer process
zhao ji hua ; chen qi yuan

..............page:73-76

A comparative study of vegetables′ absorption of NO3-N and NH+4-N
zhang shu qing ; wei xiao ping

..............page:77-84

The optimal control model of the stocking farm management of alpine meadow in Southern Gansu and research on a strategy for sustained utilization
li zi zhen ; du guo zuo ; hui cang ; yue dong xia

..............page:85-89

A study of the architecture of the pulmonary artery and capillaries in the phrynocephalus przewalskii
zhang de lu ; hu chun xiang ; yu shi yuan

..............page:90-94

Protection of transgenic chili pepper expressing cmv and tmv coat proteins gene against unrelated cmv strains and viruses
xu bing liang ; shang hong sheng ; wang xu

..............page:95-100

Quantitative analysis of the value flow in the ecological and economic integration system of the alpine meadow stocking farm
hui cang ; li zi zhen ; du guo zuo

..............page:101-104

Studies on the population dynamics of Chorthippus fallax (Zubovsky)
liu chang zhong ; wang gang ; wang wan xiong

..............page:105-108

The influence of the number of reserves on population persistence at the metapopulation level
zhou shu rong ; wang gang

..............page:109-113

Status survey and dynamic analysis of land use in urban fringe areas based on RS and GIS technology--Taking Xigu District of Lanzhou as an example
fan ze meng ; zuo yao wen

..............page:114-118

Chemical characteristic study of snow and snow pit in Mount Qomolangma region
zhang dong qi ; qin da he ; hou shu gui ; ren jia wen ; kang shi chang

..............page:119-124

A case study of space-time simulation of Lanzhou′s urban housing prices using the SD-GIS model
luo ping ; he su fang ; huang yao li ; niu hui en ; pu xin dong ; du qing yun

..............page:125-130

Dynamic and energetic diagnoses of "98.7" extraordinary heavy rainfall
feng wu hu ; cheng zuo sheng

..............page:131-137

xi tong zhong de jun heng tai wen ti --kakutani bu dong dian ding li de ying yong
chen fang

..............page:138-139

2,2- er jia ji -3- zuo ji -6- jia yang zuo ji ben bing zuo zuo de shou ci quan he cheng
xie zhi xiang ; li zuo ; hu yang ; li yu lin

..............page:140-142