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1.
X. Dupain  R. Madon  M. Makkee  J.A. Moulijn 《Fuel》2003,82(13):1559-1569
A paraffinic hydrowax feed spiked with naphthalene, anthracene, and phenanthrene was cracked in a once-through microriser reactor at 575 °C and with a catalyst-to-oil (CTO) ratio of 4.8 gcat goil−1. The conversion by cracking reactions is limited to the paraffinic fraction of the feed and the alkyl groups associated with the benzene ring in aromatic compounds; the aromatic probes did not crack under the applied conditions, and in fact an additional amount of naphthalene was formed by complex dealkylation and hydrogen transfer reactions. The ‘uncrackabilty’ of aromatics was directly demonstrated by processing an aromatic gas oil, containing 33.3 wt% aromatics. Experiments were performed with residence times between 0.05 and 8.2 s, keeping the temperature (525 °C) and CTO ratio (5.5 gcat goil−1) constant. The data was interpreted with a simplified first-order five-lump kinetic model, where approximately 19 wt% of the feed was found to be uncrackable. HCO (feedstock) conversion took mainly place during the first two seconds and coke was only formed during the first 50 ms of catalyst-oil contact. Gasoline was not overcracked to gas. Approximately 50 wt% of the LCO fraction was formed during this 50 ms and did not change thereafter.  相似文献   
2.
This research examined whether parents' and children's perceptions of one another have reciprocal self-fulfilling effects on each other's behavior. Parents and their adolescent children completed self-report surveys and engaged in dyadic videotaped interaction tasks. The surveys assessed mothers', fathers', and children's perceptions of their own and the other's hostility and warmth. Observers coded the videotaped interactions to assess the actual hostility and warmth exhibited by parents and children. Data from 658 mother-child dyads were consistent with the conclusion that children had a self-fulfilling effect on their mothers' hostility but that mothers did not have a reciprocal self-fulfilling effect on their children's hostility. No other self-fulfilling prophecy effects emerged. Findings are discussed in terms of family relations and the differential power of negative versus positive self-fulfilling prophecies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Energy-dispersive X-ray powder diffraction experiments have been investigated at high temperature and room pressure, and at high pressure and room temperature, starting from either γ- or β-Ca2SiO4. High-temperature studies were performed up to 1980 K, using a versatile heating cell. The high-temperature phase transformations previously described were reexamined. Volume and linear thermal expansions were measured for each Ca2SiO4 polymorph, γ, β, α';L,α';H, and α. Volume thermal expansion increases with increasing temperature except for α';H, whose thermal expansion tends to decrease at elevated temperature. High-pressure investigations were performed in the 0–15 GPa pressure range, using a diamond anvil cell, with silicon oil as the pressure-transmitting medium. The value of the room-pressure bulk modulus K0 , assuming a second-order BirchMurnaghan equation of state with K'0= 4, is 140(8) GPa for γ-Ca2SiO4. The γ olivine form exhibits anisotropic compression, with the c axis as the most compressible. From such in situ high-pressure X-ray investigations, the γ-→Ca2SiO4 phase transformation induced by cold compression is clearly evidenced and extends from 2 to about 5 GPa.  相似文献   
4.
This research examined whether self-fulfilling prophecy effects are mediated by self-verification, informational conformity, and modeling processes. The authors examined these mediational processes across multiple time frames with longitudinal data obtained from two samples of mother-child dyads (N? = 486; N? = 287), with children's alcohol use as the outcome variable. The results provided consistent support for the mediational process of self-verification. In both samples and across several years of adolescence, there was a significant indirect effect of mothers' beliefs on children's alcohol use through children's self-assessed likelihood of drinking alcohol in the future. Comparatively less support was found for informational conformity and modeling processes as mediators of mothers' self-fulfilling effects. The potential for self-fulfilling prophecies to produce long-lasting changes in targets' behavior via self-verification processes are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Comments on the article by Sue (December 1999; see record 1999-15532-003), in which he leveled a serious charge against the scientific community of psychology. He asserted that the enforcement of scientific criteria is selective and biased against ethnicity research. To remedy this bias, Sue proposed that the field adopt an exceptionally strong formulation of the principle of empirical skepticism that would preclude theory generalization across ethnicity and require theory testing in all populations. The ultimate challenge of psychological science is the development of universal theories that can explain individual differences both within and across cultures. Ethnicity research contributes most when it advances broad theories that apply to multiple ethnic groups. To this end, theories should include constructs that characterize multiple ethnic groups to varying degrees and should not present the ethnic group itself as an explanation for differences. The goal ought to be broader, cross-cultural theory and unification of empirical findings--not ad hoc theory and fragmentation along ethnic lines. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
7.
Recent years have seen many developing countries taking initiatives aimed at promoting decentralised planning through the application of computer-based information systems at local levels of administration. However, with all these experiments, the key objective of improving the effectiveness of development planning remains unfulfilled. A major reason for this has been the inadequate management of human resource capacity to support the intervention. The problem stems in part from the lack of skilled computer-literate people to operate the machines. This has been acknowledged in the literature. Another problem stems from the complex interaction between the social context of development administration and the process of human resource management. There is, however, a chronic paucity of studies which aim to improve understanding of this interaction. To rectify this, this paper describes a case study of the application of computers for development planning in India. The complex interaction between the social context of development administration and the process of human resources development is examined longitudinally. The findings show that an understanding of this interaction is crucial if information technology is intended to play a meaningful role in managing development.  相似文献   
8.
One of the principalcauses of present concern is the current unavailability of alternative sources of fuels for transporation. Other fuel imensive sectors, such as electric power generation, can depend on coal or nuclear fuel to provide the energy if petroleum-based fuels become scare. The transporation sector, on the other hand, is projected to need liquid fuels. Due to the relevant abundance of coal in the United States, it isimperative to find ways of converting coal to liquid fuels. Products from coal liquefaction processes contain a high aromatic content. Though this is a desirable comporent isgasoline, it is a very undersirable one in jet and diesel fuels (Table 1). In even higher boiling materials such as gas oils, the high aromatic content makes it quite difficult to produce gasoline by normal rednery processess. Fischer-Tropsch (FT)synthesis, in which carbon produces mainly straight chain aliphatic hydrogen obtained from coal gastfication are reacted over a caralyst, is the only develped coal-derived process which produces mainly straight chain aliphatic hydrocarbons. Although such aliphatic hydrocarbons are not very desirable on motor gasolines due to their low octare number, diesel and jet fuels containing such aliphatic, hydrocarbons are considered high quality materials. In addition, the higher boiling gas oil traction from the FT process is easily converted to gasoline and diesel fuel by conventional refining technology  相似文献   
9.
Seventy-three children with acute lymphoblastic leukaemia (ALL) in first bone marrow (BM) relapse, occurring within 30 months from complete remission (CR), were enrolled in an Italian cooperative study (ALL R-87 protocol). This treatment programme consisted of an induction phase with intermediate-dose cytarabine (IDARA-C) plus idarubicin (IDA) and prednisone (PDN), followed by a multidrug consolidation therapy and bone marrow transplant (BMT). 55/73 children achieved CR (75.3%); 15 (20.5%) failed to respond and three (4.2%) died during induction. The response rate was significantly higher for children with a first CR duration > or = 12 months (P=0.0005) and for those with a white blood cell (WBC) count at relapse < 20 x 10(9)/l (P=0.004). The estimated disease-free survival (DFS +/- SE) at 82 months was 0.18 +/- 0.05 for all responders, and 0.70 +/- 0.14 for allotransplanted patients versus 0.05 +/- 0.05 for those autografted (P=0.001). The estimated probabilities of survival +/- SE and event-free survival (EFS +/- SE) at 83 months were 0.16 +/- 0.07 and 0.13 +/- 0.04, respectively. for all enrolled children. Univariate analysis showed that age < 10 years at initial diagnosis and B-lineage immunophenotype favourably influenced both DFS (P=0.001) and EFS probabilities (P=0.0014 and P=0.012, respectively), whereas a first CR duration > or = 12 months and a WBC count at relapse < 20 x 10(9)/l were associated only with a better EFS rate (P=0.026 and P=0.004, respectively). Our results show the efficacy of the IDA plus IDARA-C schedule used in the ALL R-87 protocol in high-risk relapsed ALL children. Allogeneic BMT proved effective for patients with an HLA sibling donor. In a multivariate analysis, age > or = 10 years at initial diagnosis (P=0.016) and WBC count at relapse > or = 20 x 10(9)/l (P=0.048) were independently associated with a worse disease outcome.  相似文献   
10.
OBJECTIVE: To evaluate whether the addition of bismuth subnitrate to a dual oral therapy regimen with omeprazole plus amoxycillin could improve Helicobacter pylori eradication. METHODS: Fifty consecutive Helicobacter pylori-positive patients were randomly enrolled to receive either (A) bismuth subnitrate (300 mg q.d.s.), omeprazole (20 mg b.d.) and amoxycillin (500 mg q.d.s.), or (B) omeprazole (20 mg b.d.) and amoxycillin (500 mg q.d.s.). Both groups (n=25 each) received the medication for 14 days. H. pylori status was reassessed 30 days after completion of the therapy in order to evaluate eradication rates. RESULTS: Six patients were lost to follow-up and therefore excluded from the study (three patients from each group). One patient from Group B withdrew from the study because of side-effects. The addition of bismuth subnitrate to omeprazole and amoxycillin significantly improved its efficacy in eradicating H. pylori, with 72% (18/25) eradication in Group A and 52% (13/25) in Group B (P=0.027). The addition of bismuth subnitrate to dual oral therapy was also capable of improving the healing of peptic ulcers when compared with dual oral therapy alone (100%, 8/8 vs. 58%, 4/7; P=0.021). CONCLUSION: Our results demonstrate that the addition of bismuth subnitrate to dual oral therapy enhances H. pylori eradication, and improves healing of peptic ulcers.  相似文献   
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