Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Yue Deng x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

A bifunctional catalyst Pt/Hβ-n (Pt loading: 0.4 wt%) was prepared by the impregnation of an aqueous solution of chloroplatinic acid with β zeolite, wherein the β zeolite support has an unusual morphology of egg-like microspheres assembled by nanocrystallites. Other two control catalysts were also prepared using a β support with micro-sized crystals and a commercial one with varying crystal sizes. The catalysts were characterized by XRD, SEM, ICP, N2 sorption isotherms and mesopore size distribution, and evaluated in the hydroisomerization of n-heptane in an atmospheric fixed bed flow reactor. Though Pt/Hβ-n has similar acidity and Pt loading (0.4 wt%) to the two control catalysts, it exhibits remarkably higher conversion of n-heptane and selectivity to isomerization. According to the characterization data, the higher activity of Pt/Hβ-n is the result of the faster diffusion of reactants in shorter channels of nanocrystallines and the uniformly distributed mesopores within the microspheres.

Restricted access

Abstract  

This study characterized the removal of strontium from an aqueous solution via co-precipitation followed by microfiltration (CPMF) on a lab-scale. Sodium carbonate was used as the precipitating agent. Ferric chloride was added to a settler at a dosage of 20 mg/L to improve strontium removal, and it was added to a membrane separator at a dosage of 10 mg/L to reduce membrane fouling. The concentration of strontium in the raw water used in this study was about 5 mg/L. In two intermittent tests, where dosages of sodium carbonate were 2000 mg/L and 1000 mg/L, the mean decontamination factors (DFs) were 237 and 158 and the mean concentration factors (CFs) were 288 and 462, respectively. Although the mean DF value was lower when the sodium carbonate dosage was 1000 mg/L instead of 2000 mg/L, the rate at which the specific flux (SF) of the membrane declined decreased as the amount of the effluent treated increased. The problem of strontium release at the beginning of the operation was controlled by a continuous test in which the dosage of sodium carbonate still was 1000 mg/L and the other parameters were the same as in the other tests. The results showed that the mean DF and CF were 157 and 480, respectively.

Restricted access
Journal of Behavioral Addictions
Authors:
Haoran Meng
,
Hongjian Cao
,
Ruining Hao
,
Nan Zhou
,
Yue Liang
,
Lulu Wu
,
Lianjiang Jiang
,
Rongzi Ma
,
Beilei Li
,
Linyuan Deng
,
Zhong Lin
,
Xiuyun Lin
, and
Jintao Zhang

Abstract

Background and aims

Previous studies on smartphone use motivation (SUM) and problematic smartphone use (PSU) have been limited in the utilization of regional samples of emerging adults (e.g., college students) and also in the foci on the direct association between SUM and PSU. To address such gaps, using data from a large, national representative sample of Chinese young adolescents and their parents this study examined the associations between adolescents' various types of SUM and their PSU, and also tested the potential mediating roles of smartphone use time (SUT) that adolescents spent on various activities in such associations.

Methods

A nationwide representative sample of 8,261 Chinese adolescents (M age = 12.86 years old, SD = 1.76; 42.6% females) and their parents (49% mothers) participated in this survey study.

Results

Instrumental SUM (i.e., to expand knowledge or acquire information) was associated negatively with PSU via longer SUT spent on learning and shorter SUT spent on entertainment and communication. Self-expression SUM (i.e., to gain acceptance and recognition of others by maintaining or improving self-images) was associated with longer SUT spent on both learning and entertainment, which, in turn, predicted lower and higher levels of PSU, respectively. Last, hedonic SUM (i.e., to gain pleasure) was associated positively with PSU via longer SUT spent on entertainment and communication.

Discussion

These findings contribute to the literature by adding greater specificity in our understanding of the implications of SUM and SUT in the etiology of PSU during the critical life stage of adolescence in a Chinese cultural context.

Open access