PubMed Health⌕ Search

Biomedical subjects

Yi Chen

Publications and source records attributed to Yi Chen.

At least 91 records · Page 5Linked to original sources
PubMed2005

Differences in surfactant lipids collected from pleural and pulmonary lining fluids.

PURPOSE: The type and relative importance of saturated and unsaturated phospholipid components of surfactant within the epithelial lining fluid (ELF) of the inner and outer surfaces of the lung is not known. METHODS: Seven healthy dogs were anesthetized and a bronchoalveolar lavage (BAL) was performed, immediately followed by a pleural lavage (PL). Lipid was extracted from lavage fluid and then analyzed for saturated, primarily dipalmitoylphosphatidylcholine (DPPC), and unsaturated phosphatidylcholine (PC) species using high-performance liquid chromatography (HPLC) with combined fluorescence and ultraviolet detection. Dilution of ELF in lavage fluids was corrected for using the urea method. RESULTS: DPPC (494.7 +/- 213.9 microg/mL) was the predominant PC present in ELF collected from the alveolar surface. In contrast, significantly higher (p = 0.028) proportions of unsaturated PC species were measured in PL fluid (approximately 105 microg/mL), particularly stearoyl-linoleoyl-phosphatidylcholine (SLPC), which could not be measured in fluid collected from the alveoli, compared to DPPC (2.6 +/- 2.0 microg/mL). CONCLUSIONS: This study indicates that unsaturated PC species seem to be more important than saturated species, particularly DPPC, in the pleural cavity, which has implications for surfactant replenishment following pleural disease or thoracic surgery.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2005

[Duffy antigen receptor for chemokines attenuates breast cancer growth and metastasis: an experiment with nude mice].

OBJECTIVE: To study the effects of Duffy antigen receptor for chemokines (DARC) on the tumorigenesis and metastasis of breast cancer. METHODS: Human breast cancer cells of the line MDA-MB-435HM with a great potentiality of metastasis were cultured and then divided into 3 groups: MDA-MB-435HM-DARC cell group, to be transfected with pcDNA3/DARC FyB containing human DARC cDNA; MDA-MB-435HM-vect cell group, to be transfected with blank plasmid pcDNA3; and MDA-MB-435HM cell group without transfection. Female BALB/c nude mice were implanted with MDA-MB-435HM cells into the nipple. The size of the implanted cancer was measured once a week. The mice were killed 4, 6, and 8 weeks after the implantation respectively and their lungs were taken out to observe the number of metastatic tumor. Immunohistochemical staining was performed to calculate the microvascular density (MVD). Western blotting was used to detect the matrix metalloproteinase (MMP)-9 protein expression of the lung tissues. ELISA was used to detect the concentrations of the 2 DARC ligands: CNCL8 and CCL2 in the supernatant of culture fluid of the 3 kinds of cells and the metastatic tumors. RESULTS: The expression levels of DARC mRNA and protein of the MDA-MB-435HM cells were 38% those of the MDA-MB-435 cells. The expression levels of CXCL8 and CCL2 of the MDA-MB-435HM-DARC cells were significantly lower than those of the MDA-MB-435HM-vect cells and MDA-MB-435HM cells (both P < 0.05). All mice developed tumor with a tumorigenesis rate of 100%. However, the tumor occurred 17 days after implantation in those mice implanted with MDA-MB-435HM-DARC cells, significantly later then in those implanted with MDA-MB-435HM-vect cells and MDA-MB-435HM cells (9 and 10 days after implantation) the size of tumor in the former group being significantly smaller than those of the 2 latter groups (both P < 0.01). The number of metastatic foci in the lung of the MDA-MB-435HM-DARC group was significantly less than those of the other 2 groups (both P < 0.01). The level of CCI2 of the implanted tumor in the MDA-MB-435HM-DARC group was significantly lower than those of the other 2 groups (both P < 0.01). The MVD of the MDA-MB-435HM-DARC was significantly less than those of the other 2 groups (both P < 0.01) and most of the vessels of the MDA-MB-435HM-DARC group were not newly formed vessels with a diameter < 8 red blood cells. The MMP-9 protein expression levels of the MDA-MB-435HM-vect cells and MDA-MB-435HM-cells were 3.1 and 3.4 times that of the MDA-MB-435HM-DARC group (both P < 0.05). CONCLUSION: DARC, a chemokine decoy receptor, inhibits the chemokine-induced angiogenesis, thus inhibiting the growth and lung metastasis of breast cancer.

Animals↗
PubMed2005

The interaction of a new motor skill and an old one: H-reflex conditioning and locomotion in rats.

New and old motor skills can interfere with each other or interact in other ways. Because each skill entails a distributed pattern of activity-dependent plasticity, investigation of their interactions is facilitated by simple models. In a well characterized model of simple learning, rats and monkeys gradually change the size of the H-reflex, the electrical analog of the spinal stretch reflex. This study evaluates in normal rats the interactions of this new skill of H-reflex conditioning with the old well established skill of overground locomotion. In rats in which the soleus H-reflex elicited in the conditioning protocol (i.e., the conditioning H-reflex) had been decreased by down-conditioning, the H-reflexes elicited during the stance and swing phases of locomotion (i.e., the locomotor H-reflexes) were also smaller. Similarly, in rats in which the conditioning H-reflex had been increased by up-conditioning, the locomotor H-reflexes were also larger. Soleus H-reflex conditioning did not affect the duration, length, or right/left symmetry of the step cycle. However, the conditioned change in the stance H-reflex was positively correlated with change in the amplitude of the soleus locomotor burst, and the correlation was consistent with current estimates of the contribution of primary afferent input to the burst. Although H-reflex conditioning and locomotion did not interfere with each other, H-reflex conditioning did affect how locomotion was produced: it changed soleus burst amplitude and may have induced compensatory changes in the activity of other muscles. These results illustrate and clarify the subtlety and complexity of skill interactions. They also suggest that H-reflex conditioning might be used to improve the abnormal locomotion produced by spinal cord injury or other disorders of supraspinal control.

Animals↗
PubMed2005

Reactive oxygen species elicit apoptosis by concurrently disrupting topoisomerase II and DNA-dependent protein kinase.

Reactive oxygen species (ROS) are produced by all aerobic cells and have been implicated in the regulation of diverse cellular functions, including intracellular signaling, transcription activation, proliferation, and apoptosis. Salvicine, a novel diterpenoid quinone compound, demonstrates a broad spectrum of antitumor activities. Although salvicine is known to trap the DNA-topoisomerase II (Topo II) complex and induce DNA double-strand breaks (DSBs), its precise antitumor mechanisms remain to be clarified. In this study, we investigated whether salvicine altered the levels of ROS in breast cancer MCF-7 cells and whether these ROS contributed to the observed antitumoral activity. Our data revealed that salvicine stimulated intracellular ROS production and subsequently elicited notable DSBs. The addition of N-acetyl cysteine (NAC), an antioxidant, effectively attenuated the salvicine-induced ROS enhancement and subsequent DNA DSBs. Heat treatment reversed the accumulation of DNA DSBs, and the addition of NAC attenuated the Topo II-DNA cleavable complexes formation and the growth inhibition of salvicine-treated JN394top2-4 yeast cells, collectively indicating that Topo II is a target of the salvicine-induced ROS. On the other hand, when examining the impact of salvicine on DNA repair pathways, we unexpectedly observed that salvicine selectively down-regulated the catalytic subunit of DNA-dependent protein kinase (DNA-PK(CS)) protein levels and repressed DNA-PK kinase activity; both of these effects were attenuated by NAC pretreatment of MCF-7 cells. Finally and most importantly, NAC attenuated salvicine-induced apoptosis and cytotoxicity in MCF-7 cells. These results indicate that apart from its direct actions, salvicine generates ROS that modulate DNA damage and repair, contributing to the comprehensive biological consequences of salvicine treatment, such as DNA DSBs, apoptosis, and cytotoxicity in tumor cells. The finding of salvicine-induced ROS provides new evidence for the molecular mechanisms of this compound. Moreover, the effects of salvicine-induced ROS on Topo II and DNA-PK give new insights into the diverse biological activities of ROS.

Acetylcysteine↗
PubMed2005

The p53 pathway is synergized by p38 MAPK signaling to mediate 11,11'-dideoxyverticillin-induced G2/M arrest.

The phytochemical 11,11'-dideoxyverticillin, derived from the fungus Shiraia bambusicola, has been shown to possess potent anticancer activity in vitro and in vivo. Here, we investigated the effect of 11,11'-dideoxyverticillin on cell cycle progression, and explored the potential mechanisms for this effect. A concentration- and time-dependent cell cycle blockade at G2/M phase was observed in human colon cancer cells (HCT-116) following 11,11'-dideoxyverticillin treatment and was associated with marked increases in levels of p53, phospho-p53(ser20) and phospho-Chk2(Thr 68). When wild type p53 expression was specifically inhibited by RNA interference, HCT-116 cells treated with 11,11'-dideoxyverticillin failed to arrest in G2/M and did not show increased phospho-Chk2(Thr 68). On the other hand, 11,11'-dideoxyverticillin treatment also elicited p38 MAP kinase activity and expression of phospho-p38 MAPK. Treatment with a specific p38 MAPK inhibitor (SB203580) successfully inhibited p38 MAPK and delayed the onset of G2/M arrest induced by 0.5 microM 11,11'-dideoxyverticillin after approximately 6 h, but did not abolish the induction of G2/M arrest. Additionally, SB203580 did not alter the levels of p53, phospho-p53 (ser20), or phospho-Chk2 (Thr68) proteins in 11,11'-dideoxyverticillin-treated cells. Together, these findings indicate that p53-mediated phosphorylation of Chk2 maybe plays a vital role in 11,11'-dideoxyverticillin-induced G2/M arrest, and that p38 MAPK might accelerate this progression. Our work suggests a new possibility of interactions among p53, Chk2 and p38 MAPK signaling in G2/M arrest.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Synthesis and antitumor activity of the hexacyclic camptothecin derivatives.

A series of hexacyclic camptothecin derivatives were synthesized to test for antitumor activity as topoisomerase I inhibitor. The strategy of synthesis was used for the formation of additional furan and dihydrofuran rings fused with 9- and 10-positions of camptothecin. All of the hexacyclic camptothecins were assayed for cytotoxicity against four human tumor cell lines, HL60, BEL-7402, HCT-116, and HeLa, and showed very impressive cytotoxicity activity in vitro. Enzyme activity of the hexacyclic camptothecins was evaluated, being equal or superior to that of SN-38. The stability of four compounds was assessed in human plasma. Two of these compounds were chosen to test for antitumor activity in vivo against Sarcoma-180. The results suggested that additional furan and dihydrofuran rings could improve the antitumor activity in vitro and vivo, though the stability of the lactone ring did not increase.

Animals↗
PubMed2005

Resveratrol inhibits neuronal discharges in rat hippocampal CA1 area.

The effects of resveratrol on the discharges of neurons in CA1 area of rat hippocampal slices were examined by using extracellular recording technique. The results are as follows: (1) In response to the application of resveratrol (0.05, 0.5, 5.0 micromol/L, n=52) into the superfusate for 2 min, the spontaneous discharge rate of 46/52 (88.5%) neurons was significantly decreased in a dose-dependent manner; (2) Application of L-glutamate (0.2 mmol/L) into the superfusate led to a marked increase in discharge rate of all 8 (100%) slices in an epileptiform pattern. The increased discharges were suppressed by application of resveratrol (5.0 micromol/L); (3) In 7 slices, perfusion of the selective L-type calcium channel agonist, Bay K8644 (0.1 micromol/L), induced a significant increase in the discharge rate of 6/7 (85.7%) slices. The increased discharges were suppressed by application of resveratrol (5.0 micromol/L); (4) In 9 slices, perfusion of nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 50 micromol/L) into the superfusate significantly augmented the discharge rate of 7/9 (77.8%) slices. Resveratrol (5.0 micromol/L) applied into the superfusate reduced the increased discharges of all 7/7 (100%) neurons; (5) In 10 units, the large-conductance Ca(2+)-activated K(+) channel blocker (tetraethylammonium chloride, TEA, 1 mmol/L) significantly increased the discharge rate of 9/10 (90%) slices. Resveratrol (5.0 micromol/L) applied into the superfusate inhibited the discharges of 8/9 (88.9%) slices. These results suggest that resveratrol inhibits the electrical activity of CA1 neurons. This effect may be related to the blockade of L-type calcium channel and a subsequent reduction of calcium influx, and probably has no association with large-conductance Ca(2+)-activated K(+) channel.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed2005

Study on photochromism of diarylethenes with a 2,5-dihydropyrrole bridging unit: a convenient preparation of 3,4-diarylpyrroles from 3,4-diaryl-2,5-dihydropyrroles.

Symmetric and nonsymmetric diarylethenes with a 2,5-dihydropyrrole bridging unit have been prepared, and the photochromic properties are investigated. Both symmetric and nonsymmetric diarylethenes with 2,5-dihydropyrrole bridging units undergo reversible ring-opening and ring-closing photoisomerization reactions in nonpolar solvents with UV/vis light, and some of them exhibit good fatigue resistance and no marked degradation detected after 10 cycles via an on/off switch. In polar solvents, however, photochromic diarylethenes with 2,5-dihydropyrrole bridging units produce 3,4-diarylpyrrole derivatives instead of the ring-closing isomer of diarylethenes with UV light irradiation. A class of N-substituted 3,4-diphenylethenes with 2,5-dihydropyrrole bridging units were prepared and used as templates to investigate the conversion reactions. The mechanism of photoconversion of 3,4-diaryl-2,5-dihydropyrroles to 3,4-diarylpyrroles was explored as well.

Journal Article↗
PubMed2005

Dispersion behaviors of molybdena on titania (rutile and/or anatase).

Raman and FT-IR spectra were employed to investigate the dispersion of molybdena on mixed TiO2 (rutile and anatase, signed as R and A) with different BET surface ratios of rutile/TiO2(R + A). The results showed that (1) molybdena would preferentially disperse on the rutile surface in mixed TiO2; (2) for MoO3/rutile with low molybdena loading (e.g., 0.20 mmol/100 m2 rutile), a dispersed molybdena species existed on the rutile surface in an isolated tetrahedral coordination environment, while for MoO3/rutile with high molybdena loading (e.g. 0.82 mmol/100 m2 rutile), a polymeric molybdena species could be detected on the rutile surface; (3) for the MoO3/anatase sample, a dispersed molybdena species existed on the anatase surface in a polymeric coordination environment; and (4) the formation of the Bronsted acid site on the surface of rutile and anatase should be related to the polymeric molybdena species. All these results have been discussed via the interaction between OH groups of molybdena and OH groups of rutile and anatase, and it seems reasonable to suggest that, for the lower molybdena loading, the different states of the dispersed molybdena species should result from the different dehydration orders of OH groups of the molybdena and surface OH groups of rutile and anatase.

Molybdenum↗
PubMed2005

AlN nanotube: round or faceted?

Theoretical studies on one-dimensional AlN nanostructures have been performed. A faceted instead of cylindric model is proposed to reasonably understand the synthesized hexagonal AlN nanotubes. The close correlation is established that the nanotube structure should possess similar symmetry to that of the corresponding bulk crystal. This is also suitable for the few other faceted nanotubes and could be used to predict the morphology for the increasing nanotubes from nonlayered materials.

Journal Article↗
PubMed2005

Antiangiogenic activity of 11,11'-dideoxyverticillin, a natural product isolated from the fungus Shiraia bambusicola.

The fungus Shiraia bambusicola yields the phytochemical 11,11'-dideoxyverticillin, which has been shown to possess potent anticancer activity both in vitro and in vivo. In this study, we reveal that 11,11'-dideoxyverticillin has anti-angiogenic activities and explore the potential mechanisms for this effect. Treatment with 11,11'-dideoxyverticillin inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) with IC(50) values of 0.17+/-0.05muM for VEGF-stimulated cells and 0.39+/-0.08muM for serum-stimulated cells. 11,11'-Dideoxyverticillin also antagonized the antiapoptotic effects of VEGF on serum-deprived HUVECs, inhibited VEGF-induced HUVEC migration in vitro, and blocked serum-induced HUVEC tube formation. Moreover, 11,11'-dideoxyverticillin completely blocked VEGF-induced microvessel sprouting from Matrigel-embedded rat aortic rings and vessel growth in Matrigel plugs in mice. In addition, 11,11'-dideoxyverticillin decreased VEGF secretion by MDA-MB-468 breast cancer cells, and significantly suppressed VEGF-induced tyrosine phosphorylation of Flt-1 and KDR/Flk-1. This inhibition of receptor phosphorylation was correlated with a marked decrease in VEGF-triggered pERK activation and a dramatic increase in pP38 MAPK, but no apparent change in pAkt. Together, these findings strongly suggest that 11,11'-dideoxyverticillin is a structurally novel angiogenesis inhibitor.

Angiogenesis Inhibitors↗
PubMed2005

Synthesis and antitumor activity of 7-ethyl-9-alkyl derivatives of camptothecin.

A series of new camptothecin derivatives, as topoisomerase I inhibitor, were synthesized to identify potent antitumor agents. The synthesis method was based on the Claisen rearrangement of 10-allyloxy-7-ethylcamptothecin. All of the compounds were assayed for cytotoxicity against two human tumor cell lines, Bel7402, HCT116, and showed good potency in vitro. Compounds 2, 4, 9, were assessed for the stability of lactone in human plasma. And then compound 2 was tested for antitumor activity in vitro against mouse tumor sarcoma-180. The results suggested that the small alkyl groups in the both 7- and 9-positions of camptothecin could promote liposolubility, antitumor activity in vitro and vivo, though did not bring much increase of the stability of lactone.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Study on the pathophysiologic basis of classification of 'spleen' deficiency in chronic gastritis.

BACKGROUND: Most of the studies on traditional Chinese medicine (TCM) 'spleen' deficiency syndrome in the recent 30 years were conducted only on the basis of single functional index, neglecting the study on the pathophysiologic internal relationship between spleen deficiency syndrome and gastric diseases in modern medicine. But it was at the subcellular molecular biological level that we explored the pathophysiologic basis of classification of spleen deficiency in chronic gastritis by detecting the bioactive substances in gastric mucosa nuclei and mitochondria. METHODS: By means of optical microscope, scanning electron microscope (SEM), transmission electron microscopy (TEM) and histochemical staining, we conducted histopathological, subcellular ultrastructural analysis and nuclei and mitochondrial ultrastructural analysis of gastric mucosa of 188 spleen deficiency patients and of 42 voluntary blood donors. At the same time, bioactive substances were measured by means of X-ray energy dispersive analysis system (EDAX) image analysis system, radioimmunoassay method and chemiluminescence method. RESULTS: The content of cAMP, superoxide dismutase (SOD), Zn and Cu in gastric mucosa, and the content of Zn and Cu in mitochondria decreased progressively in order of groups: healthy control (HC), spleen Qi deficiency without organic lesion (F-SQD), spleen Yang deficiency without organic lesion (F-SyangD), disease without symptoms group, spleen Qi deficiency with organic lesion (G-SQD), spleen Yang deficiency with organic lesion (G-SyangD), spleen Yin deficiency (SyinD) and spleen deficiency with Qi stagnation (SDQS), chronic spleen deficiency gastritis (CSG) and chronic atrophic gastritis (CAG); decreased in order of HC, intestinal metaplasia (IM)Ia, IMIb, IMIIa and IMIIb, P < 0.05. The content of DNA, Zn and Cu in nuclei progressively increased in order mentioned above, P < 0.05. CONCLUSIONS: The quantitative changes of gastric mucosal cAMP, SOD, Zn, Cu, of mitochondrial Zn, Cu and of nuclear DNA, Zn and Cu are not only the substance base on which the lesion of gastric mucosa tissue structure occurs, but also the substance base on which spleen deficiency is classified. G-SQD and G-SyangD were more likely to be found in low-grade or middle-grade CSG and CAG, while SyinD and SDQS in middle-grade or high-grade CSG, CAG and IMIIb.

Adult↗
PubMed2005

Case-control association study of the close homologue of L1 (CHL1) gene and schizophrenia in the Chinese population.

The close homolog of L1 (CHL1), located on human chromosome 3p26.1, is a newly identified member of the L1 family of cell adhesion molecules which play important roles in cell migration, axonal growth, and synaptic remodeling. A positive association has been reported between a missense polymorphism in CHL1 gene and schizophrenia in the Japanese population [Sakurai, K., Migita, O., Toru, M., Arinami, T., 2002. An association between a missense polymorphism in the close homologue of L1 (CHL1, CALL) gene and schizophrenia. Mol. Psychiatry 7, 412-415]. An association between a missense polymorphism in the close homologue of L1 (CHL1, CALL) gene and schizophrenia. In order to test this finding, we genotyped four SNPs in the gene in the Han Chinese population using a sample of 560 cases and 576 controls. Analysis of allele frequencies in both samples also showed strong association between SNP rs2272522 (the same marker studied by K. Sakurai) and the disease (X2=31.591, P<0.000001, OR=1.745, 95% CI=1.435-2.121). Our results confirm the positive association between CHL1 gene and schizophrenia and indicate that CHL1 may be involved in the etiology of schizophrenia.

Adult↗
PubMed2005

Vapor-solid growth and characterization of aluminum nitride nanocones.

Aluminum nitride nanostructures are attractive for many promising applications in semiconductor nanotechnology. Herein we report on vapor-solid growth of quasi-aligned aluminum nitride nanocones on catalyst-coated wafers via the reactions between AlCl3 vapor and NH3 gas under moderate temperatures around 700 degrees C, and the growth mechanism is briefly discussed. The as-prepared wurtzite aluminum nitride nanocones grow preferentially along the c-axis with adjustable dimensions of the sharp tips in the range of 20-60 nm. The photoluminescence spectrum reveals a broad blue emission band with a fine photon structure while the field emission study shows a notable emission current with a moderate turn-on field as expected, suggesting their potential applications in light and electron emission nanodevices.

Journal Article↗
PubMed2005

Correlates of HIV status among injection drug users in a border region of southern China and northern Vietnam.

This article presents an analysis of the correlates of HIV status among samples of injection drug users (IDUs) in Lang Son Province, Vietnam (n=348), and Ning Ming County, Guangxi Province, China (n=294), who were interviewed and tested for HIV antibody just before the start of a peer-based HIV prevention intervention in this border region. Participants were largely male, in their 20s, and single. Logistic regression analysis suggests that among Chinese IDUs, border-related factors (eg, living closer to the border, buying drugs across the border more frequently) and younger age are the best predictors of HIV positivity. In Vietnam, HIV status seems to drive behavior (eg, some risk reduction practices are predictive of HIV positivity). These differing patterns may reflect the fact that the intertwined epidemics of heroin injection and HIV began earlier and HIV prevalence has reached significantly higher levels in Lang Son than across the border in Ning Ming. Although border-related factors emerge as predictors in Ning Ming, more IDUs in Lang Son are HIV-positive and may be reacting behaviorally to that status. Their greater likelihood of engaging in risk reduction measures may reflect some combination of a belief that risk reduction can slow disease progression and an altruistic desire to avoid infecting others.

Adult↗
PubMed2005

Characterization of CuO supported on tetragonal ZrO2 catalysts for N2O decomposition to N2.

A series of tetragonal zirconia-supported CuO oxide catalysts with various CuO loadings were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron spin resonance (ESR), ultraviolet and visible diffuse reflectance spectroscopy (UV/vis-DRS), and temperature-programmed reduction (TPR) measurements. The results indicate that the dispersion capacity of copper oxide on this support is approximately 8.6 Cu(2+) ions/nm(2) ZrO(2). The state of the resulting supported copper species depends on the CuO loading. At CuO loadings below the dispersion capacity, only highly dispersed copper ion species are present on the surface of t-ZrO(2). In particular, isolated Cu ions are the predominant species at low loadings. In contrast, pair Cu ions become the most abundant species at loadings near the dispersion capacity. It has been proposed that these dispersed CuO (isolated and paired Cu ions) have a symmetric 5-fold-oxygen-coordination symmetry (C(3)(v) symmetry) and can be described as distorted octahedra with a missing corner or a trigonal bipyramids. Finally, at CuO loadings above the dispersion capacity the formation of crystalline CuO is observed. TPR results reveal that the dispersed Cu ion species have a different reducibility from CuO crystallites, presumably due to strong interactions between these species and the t-ZrO(2) support. The catalytic activity of these CuO/t-ZrO(2) catalysts for the decomposition of N(2)O can also be directly correlated to CuO dispersion, with paired Cu ions being the most active species for this reaction.

Journal Article↗