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排序方式: 共有180条查询结果,搜索用时 15 毫秒
1.
G Makrydimas D Lolis I Georgiou C Skendou KH Nicolaides 《Canadian Metallurgical Quarterly》1997,6(6):314-316
For psychological reasons, coelocentesis was performed in 20 women prior to termination of pregnancy, at 6-11 weeks of gestation. The fetal heart rate (FHR) was measured immediately before the procedure and at 1, 5, and 10 min afterward. There was no significant difference between FHR before coelocentesis compared to the values at 1 min (mean = 158, range 114-178; z = -0.629, P = 0.529), 5 min (mean = 160, range 121-179; z = -0.191, P = 0.848), or 10 min (mean 159, range 117-183; z = -0.214, P = 0.83) after the procedure. These findings suggest that coelocentesis does not have a major effect on the fetal cardiovascular system. 相似文献
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4.
P Kaminopetros E Jauniaux P Kane M Weston KH Nicolaides DJ Campbell 《Canadian Metallurgical Quarterly》1997,70(835):750-753
An unusual case of fetal lymphangioma diagnosed before delivery is reported in a second trimester pregnant woman. The lymphangioma was suspected at 28 weeks on the basis of the ultrasound appearances and progression of the lesions with advancing gestation. MRI was used to evaluate the extent and the tissue characteristics of the lesions. Cytology of the fluid aspirated from the cystic lesions showed abundant lymphocytes and macrophages, confirming the diagnosis of a lymphangioma. The parents opted for a pregnancy termination because of the rapid growth of the lesions and the poor prognosis. It is suggested that the combination of these tests could enable the early diagnosis of these tumours at a stage when the lesion is relatively limited and accessible to therapy in utero. 相似文献
5.
FA Casavilla J Rakela S Kapur W Irish J McMichael AJ Demetris TE Starzl JJ Fung 《Canadian Metallurgical Quarterly》1998,4(6):448-454
In 1994, as a result of both programme evaluations which identified students' fears and apprehensions about their practical ability, and a review of the literature on skill acquisition, experiential skills teaching was resumed within the faculty. Having invested considerable finance into the reconstruction of a skills centre to teach skills, it is now imperative that its use be formally evaluated. Part of the evaluative process includes a review of the empirical literature on the acquisition of psychomotor skills in nursing. This paper summarizes this review. 相似文献
6.
We report two patients where the finding of isolated fetal hydrocephalus led to the detection of severe fetal thrombocytopenia, using fetal blood sampling. Serological investigation led to the diagnosis of fetomaternal alloimmune thrombocytopenia (FMAIT) due to anti-HPA-1a. Both women had had previous unsuccessful pregnancies probably due to FMAIT; one had had four miscarriages at 17-18 weeks' gestation. The other had had one previous pregnancy complicated by severe fetal anaemia, and eventually hydrocephalus developed and the fetus died without the diagnosis of FMAIT being considered. Subsequent pregnancies in the two women were also affected by FMAIT, but prenatal treatment, predominantly with serial fetal platelet transfusions, resulted in a successful outcome in both cases. These observations suggest that FMAIT should be suspected if there is isolated fetal hydrocephalus, unexplained fetal anaemia, or recurrent miscarriages. The accurate diagnosis of FMAIT is important because recent advances in prenatal management can improve the outcome of subsequently affected pregnancies. 相似文献
7.
Three groups of diesters have been isolated and identified in the lipids of steer meibomian glands. The first group, designated
as α Type I, with the abbreviated formula FA-αOHFA-FA1c, consisted of α-hydroxy fatty acids esterified to fatty acids and
fatty alcohols in the approximate molar ratio 1∶1∶1. The second group, designated as ω Type I-St, with the abbreviated formula
FA-ωOHF A-St, consisted of ω-hydroxy fatty acids esterified to fatty acids and sterols in the approximate molar ratio 1∶1∶1.
The third group, designated as α,ω Type II, with the abbreviated formula FA-α,ωdiol-FA, consisted of α,ω-diols esterified
to 2 moles of fatty acids. The sum of the different diesters comprised about 9% of total steer meibomian lipids.
Capillary GLC of the fatty acids of αType I diesters showed the fatty acids to be a family with a two-cluster profile, one
at C12 to C20 and the other at C21 to C31, with anteiso chains predominating. Fatty acids from ωType I-St and α,ωType II diesters gave mainly a one-cluster profile
in the short long chain, C23 to C30, with anteiso chains predominating, while the α-hydroxy fatty acids were short chain C13 to C18 acids with C16 predominating. The sterols in diesters ωType I-St were cholesterol (∼60%), Δ7 cholestenol (∼35%) and an unidentified compound
(∼5%) with a GLC retention time slightly longer than Δ7 cholestenol on SE-30 phase. The ω-hydroxy fatty acids and α,ω-diols
both were of exceedingly long chain lengths, C29−C38, and showed similar GLC profiles. Two types of triesters comprising approximately 1% of total steer meibomian lipids have
been isolated but incompletely characterized. In terms of molar ratios, one group of triesters gave fatty acids:ω-hydroxy
fatty acids:α-hydroxy fatty acids:sterols + fatty alcohols as approximately 1∶1∶1∶1. The other contained fatty acids, α-hydroxy
fatty acids and α,ω-diols in what appears to be a complex mixture of several triesters. Diesters ωType I and α,ωType II also
were found in human meibum. Hitherto these two diesters have not been found in any animal tissue. 相似文献
8.
Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished
by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates
and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix
caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C11 to C30, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched.
A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or
Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes
of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol
ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were
largely branched and of lengths greater than C18, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns,
the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and
11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to
7–8 C2 units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be
derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands
only. 相似文献
9.
Ion exchange of HZSM-5 samples with alkali metal cations, using metal chloride solutions, results in partially exchanged zeolites, MHZSM-5, M = Li, Na, K or Cs. The degree of exchange is found to increase with increasing ionic radius of the cations. The catalytic properties of the alkalized zeolites were evaluated using the reaction conditions under which the catalytic activity of the HZSM-5 samples in terms of n-hexane cracking is proportional to the aluminium content. From the residual catalytic activity exhibited by the Na-, K- and CsHZSM-5 samples it is concluded that each of the larger Na+, K+ and Cs+ ions is influencing more than one AlO
4
–
tetrahedron, implying that the aluminium sites in ZSM-5 are not isolated. The ion-exchange results are then interpreted in terms of non-isolated aluminium sites. The ion-exchange and catalytic properties of the zeolites as a function of aluminium content are also discussed. 相似文献
10.
Demetris Zarris Marianna Vlastara Dionysia Panagoulia 《Water Resources Management》2011,25(14):3785-3803
Nestos River flows through Bulgaria and Greece and discharges into the North Aegean Sea. Its total catchment area is around
6,200 km2, while the mean annual precipitation and runoff are 680 mm and 40 m3/s, respectively. The Hellenic part of the catchment has undergone a substantial hydroelectric development, since two dams
associated with major hydropower pumped-storage facilities are in operation. The main objective of the paper is to assess
the expected sediment delivery of Nestos R. at the uppermost Thisavros reservoir site. This has been carried out by implementing
the Universal Soil Loss Equation in a GIS environment for determining the mean annual soil erosion in conjunction with a suspended
sediment measurement program (114 measurements in total) accomplished between 1965 and 1983 adjacent to the dam site. The
sediment discharge rating curve between sediment and river discharges in a power form has been constructed using five alternative
techniques, namely (a) the linear regression of the log-transformed variables, (b) the same as (a) but with the Ferguson correction,
(c) different ratings for the dry and wet seasons of the year, (d) the nonlinear regression, and (e) the broken line interpolation
that utilizes different rating parameters for two discharge classes. It is shown that the mean annual sediment yield is almost
equal for all rating curve formulations and varies between 178.5 t km−2 and 203.4 t km−2 and the highest value results from the broken line interpolation method. Accordingly, the sediment delivery ratios vary slightly
between 17% and 19% of the upstream soil erosion. 相似文献