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PubMed1986

Reactive synovitis after silicone arthroplasty.

A number of patients with silicone rubber implants performed by us and other surgeons initially had excellent results; however, they returned with swelling and discomfort. We studied 18 patients ranging in age from 16 years to 57 years who presented 8 to 78 months (average, 31.7 months) after silicone arthroplasty (four scaphoid, six lunate, one scapholunate, four finger, two wrist, one trapezium, and one ulnar head for metacarpal hemiarthroplasty). Erosive osteolysis was seen on x-ray films, with progressive destruction evident in patients followed serially. None of the patients' conditions responded to conservative care. The severity of the proliferative, inflammatory synovitis and the foreign material in the multinucleated giant cells correlated with the interval since arthroplasty. Implant surface analysis by scanning electron microscope and x-ray spectrometer showed that silicone microparticles were the result of implant degeneration and erosion. All joint cultures were negative. Silicone particulate synovitis and destruction were arrested by the removal of the implant, a synovectomy, and curettage of the lytic lesions at salvage (resection arthroplasty or arthrodesis). Patients who have had silicone arthroplasties should be followed indefinitely, at regular intervals, by x-ray films and clinical examination.

Adolescent↗
PubMed1986

Silicone rubber carpal implants: a study of the incidence of late osseous complications.

This clinical review of 53 silicone rubber carpal implants done by the senior author (P. R. C.) between 1976 and 1983 determines the incidence of so-called "silicone rubber synovitis." Although previously reported in small series, the true incidence of this complication of wear of the implant has not been documented. In this study late radiographic follow-up demonstrated lytic lesions adjacent to the carpal implants in 75% of the scaphoid implants, 55% of the lunate implants, and 75% of the scapholunate implants. In patients with x-ray film evidence of lytic lesions, more than half (56%) complained of pain, and more than one fourth (27%) have already had revision surgery. In every patient who had reoperation in this study, the histologic examination of the tissue in the wrist showed a chronic granulomatous process identical to that previously reported in cases of so-called "silicone rubber synovitis". These "lytic lesions" must be differentiated from "degenerative cysts" that are a part of the natural progression of degenerative arthritis. Four cases were submitted for mass spectrophotometric analysis, and the positive identification of the silica atom was made in all four. This study shows that the wear of carpal bone implants of silicone rubber and subsequent "silicone rubber synovitis" are common occurrences and not rare as has been previously inferred from isolated case report studies. This study suggests that implantation of these implants in young, healthy individuals is rarely indicated, and careful follow-up of patients who already have these implants in place is important.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1996

In vivo inflammatory response to silicone elastomer particulate debris.

Silicone elastomer particles (Silastic silicone elastomer, Dow Corning, Midland, MI), polymethylmethacrylate particles, and monosodium urate particles smaller than 10 microns were injected into a rat subcutaneous air pouch lined with synovial membrane-like cells. Inflammatory exudate from the air pouch was retrieved at 6 hours, 24 hours, 48 hours, and 72 hours after injection. White blood cell count, tumor necrosis factor, and prostaglandin E2 were measured in the exudate. White blood cell and tumor necrosis factor levels in the exudate were the highest for the silicone group at 6 and 24 hours. Prostaglandin E2 was also significantly higher in the silicone group at 24 hours. We conclude that the acute inflammation is particle-type specific and that Silicone elastomer particles are acutely inflammatory.

Animals↗
PubMed2000

High-performance liquid chromatographic determination of 17beta-estradiol and 17beta-estradiol-3-acetate solubilities and diffusion coefficents in silicone elastromeric intravaginal rings.

A rapid, sensitive reversed-phase high-performance liquid chromatographic method has been developed for the determination of in vitro release of 17beta-estradiol and its ester prodrug, 17beta-estradiol-3-acetate, from silicone intravaginal rings. Partial hydrolysis of the acetate under the aqueous conditions provided by the 1% benzalkonium chloride release medium necessitates its conversion to 17beta-estradiol prior to HPLC analysis. Both steroid peaks have been fully resolved from the benzalkonium chloride peaks by the reported chromatographic method, which employs a C18 bonded reversed-phase column, an acetonitrile-water (50:50, v/v) mobile phase and a UV detection wavelength of 281 nm. The peak area versus 17beta-estradiol concentration was found to be linear over the range of 0.0137-1347 microkg ml(-1). The HPLC method has also been used to determine the silicone solubilities and diffusion coefficients of the two related steroids. The almost 100-fold increase in 17beta-estradiol-3-acetate release from the silicone core-type intravaginal rings compared to 17beta-estradiol is shown to be due to a 60-fold increase in silicone solubility and a one and a half-fold increase in diffusitivity. The results demonstrate that an effective estrogen replacement therapy dose of 17beta-estradiol may be administered from a silicone intravaginal reservoir device containing the labile 17beta-estradiol-3-acetate prodrug.

Administration, Intravaginal↗
PubMed1999

Functional recovery following nerve injury and repair by silicon tubulization: comparison of laminin-fibronectin, dialyzed plasma, collagen gel, and phosphate buffered solution.

PURPOSE: This study was designed to investigate the potential for enhancement of peripheral nerve regeneration by the manipulation of the neural microenvironment with laminin-fibronectin solution (LF), dialyzed plasma (DP), collagen gel (CG), or phosphate buffered saline (PBS) in a silicon tubulization repair model. METHOD: A rat sciatic nerve model of injury and repair was used to study the effects of exogenous matrix precursors (contained in LF or DP), CG or PBS on nerve regeneration. A total of 50 Sprague-Dawley rats underwent left sciatic nerve transection and repair by silicon tubulization. The silicon tubules were either left empty (E), or filled with solutions of LF, DP, CG, or PBS. Nerve function was assessed preoperatively and then postoperatively, every 10 days for 90 days using sciatic functional indexes (SFI). On postoperative day 90, the sciatic nerves were harvested for histologic analysis and the posterior compartment muscles of each animal were harvested and weighed. Molecular analysis for two proteins associated with neural regeneration was performed on the nerve segments. RESULTS: All five animal groups demonstrated equivalent functional recovery. Comparison of the rate of recovery and mean maximal recovery between each group revealed no statistically significant differences, with P-values ranging from 0.30 to 0.95. Posterior compartment muscle masses were similar in all groups except for LF, whose animals had muscle masses 8-9% lower than CG, PBS, or E (P < 0.05). CONCLUSION: Alteration of the regenerating neural microenvironment with exogenous matrix precursors (LF, DP), CG or PBS failed to improve sciatic functional recovery after nerve transection and silicon tubulization in this model. From this study, we conclude that LF, DP, CG, and PBS do not enhance the rate or degree of recovery of peripheral nerve function across a narrow gap when nerves are repaired by silicon tubulization.

Animals↗
PubMed2002

Uveal and capsular biocompatibility of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses.

PURPOSE: To evaluate the long-term response of 6 types of 3-piece intraocular lenses (IOLs) by assessing the cellular reaction on the anterior IOL surface, the behavior of posterior and anterior capsule fibrosis, and flare. SETTING: Department of Ophthalmology, Medical School, University of Vienna, Vienna, Austria. METHODS: One hundred eighty eyes were prospectively randomized to receive 1 of 6 IOLs: hydrophilic acrylic Hydroview (Bausch & Lomb) or MemoryLens (ORC); hydrophobic acrylic AcrySof MA60BM (Alcon) or AMO Sensar AR40 (Allergan); hydrophobic silicone CeeOn 920 or CeeOn 911A (Pharmacia). The patients had standardized cataract surgery, postoperative medication, and follow-up. One year after surgery, 155 eyes were assessed. The cellular reaction was evaluated by specular microscopy of the anterior IOL surface. Anterior and posterior capsule opacification (PCO) was assessed semiquantitatively by biomicroscopy. Flare was measured with a Kowa FC-1000 laser flare-cell meter. RESULTS: Regarding uveal biocompatibility, the hydrophobic acrylic IOLs showed the highest incidence of late foreign-body cell reaction (AcrySof, 30%; AR40, 17%) followed by the hydrophilic acrylic (MemoryLens, 8%; Hydroview, 4%) and silicone (CeeOn 920, 4%; CeeOn 911A, 0%) (P =.0044). In all cases, the cellular reaction was low grade and clinically insignificant. Regarding capsular biocompatibility, some eyes developed lens epithelial cell (LEC) outgrowth on the anterior IOL surface. The highest incidence was in the hydrophilic acrylic group (Hydroview, 85%; MemoryLens, 27%) followed by the hydrophobic acrylic (AcrySof, 4%; AR40, 3%). No silicone IOL had LECs on the anterior surface. The difference among IOL groups was significant (P =.0001). Anterior capsule opacification was more predominant in the hydrophobic IOL groups. Posterior capsule opacification of the central 3.0 mm area was lowest in the groups with a sharp-edged optic (CeeOn 911A, AcrySof) followed by the round-edged silicone (CeeOn 920), hydrophobic acrylic (AR40), and hydrophilic acrylic IOLs (P =.0001). There was a significant difference in flare between the AR40 lens and the Hydroview, MemoryLens, CeeOn 911A, and CeeOn 920 (P <.004). There was no statistically significant difference in the postoperative cell count at 1 year. The power calculation showed that the sample size was sufficient. CONCLUSIONS: The differences in cellular reaction, although clinically mild in normal eyes, indicate that there were more giant cells with hydrophobic acrylic IOLs and an increased tendency toward LEC outgrowth with hydrophilic lenses. The incidence of PCO was lowest in the hydrophobic IOL groups, especially in groups with a sharp-edged optic. Second-generation silicone IOLs with a sharp edge had good uveal and capsular biocompatibility 1 year after surgery.

Acrylic Resins↗
PubMed2003

After-cataract in adults with primary posterior capsulorhexis: comparison of hydrogel and silicone intraocular lenses with round edges after 2 years.

PURPOSE: To evaluate the potential of primary posterior continuous curvilinear capsulorhexis (PCCC) to prevent after-cataract 2 years after surgery and perform a bilateral comparison of 2 intraocular lens (IOL) materials, silicone and hydrogel. SETTING: Department of Ophthalmology, University of Vienna, Medical School, Vienna, Austria. METHODS: In this randomized patient- and examiner-masked study, 37 patients (74 eyes) with age-related cataract had bilateral small-incision cataract surgery with PCCC. Randomly, 1 eye received a hydrogel IOL and the contralateral eye, a silicone IOL. Both IOLs had open-loop haptics and a round-edged optic. Standardized digital retroillumination photographs were taken 1 day and 1, 6, 12, and 24 months after surgery to evaluate development of after-cataract on the anterior and posterior capsules by subjective grading. Opacification of the PCCC area was also objectively evaluated using new software. RESULTS: Twenty-nine patients (58 eyes) completed the 2-year follow-up. Partial closure with ongrowth at the edge of the PCCC was found in 55% in the hydrogel group and 28% in the silicone group. Total closure of the PCCC was observed in 3 eyes, 2 in the hydrogel group and 1 in the silicone group. CONCLUSION: Ongrowth onto the PCCC area was dependent on IOL material. Because of less ongrowth and more fibrotic after-cataract with silicone IOLs, the efficacy of the PCCC was higher in this group.

Aged↗
PubMed2003

Posterior capsule opacification: silicone plate-haptic versus AcrySof intraocular lenses.

PURPOSE: To evaluate posterior capsule opacification (PCO) in fellow eyes, 1 receiving a silicone intraocular lens (IOL) and the other, an acrylate IOL. SETTING: Department of Ophthalmology, Isala Clinics, Zwolle, The Netherlands. METHODS: This retrospective study comprised 107 patients (214 eyes). In each patient, 1 eye was randomly selected to have implantation of an acrylate IOL (AcrySof MA30BA or MA60BM, Alcon) and the other eye, a plate-haptic silicone IOL (AA4203VF, Staar). Outcome measures were the total PCO index, percentage of neodymium:YAG (Nd:YAG) capsulotomies performed, and logMAR best corrected visual acuity (BCVA). The follow-up was 3 years. RESULTS: The total PCO index was significantly lower in the AcrySof group than in the plate-haptic silicone group (P<.0001). There was no significant difference in logMAR BCVA between groups (P>.05). The percentage of Nd:YAG laser treatments was significantly lower in the AcrySof group (2.8%) than in the plate-haptic silicone group (23.1%) (P<.05). CONCLUSIONS: There was significantly less PCO and a lower Nd:YAG laser capsulotomy rate after AcrySof IOL implantation than after plate-haptic silicone IOL implantation. These results did not seem to affect the logMAR BCVA as there were no significant differences between groups in this parameter.

Acrylic Resins↗
PubMed1987

Complications associated with STAAR silicone implants.

We compared the incidence of various complications in consecutive series of cases in which 76 eyes received STAAR silicone intraocular implants and 76 eyes received small incision IOLAB G708G polymethylmethacrylate (PMMA) intraocular implants. All surgeries were performed by the same surgeon employing the same phacoemulsification technique. A higher incidence of lens subluxation, lens repositioning, corneal edema, and elevated intraocular pressure was observed in the eyes receiving STAAR silicone implants than in the eyes receiving IOLAB PMMA implants. In addition, a YAG laser posterior capsulotomy could not be performed through several STAAR silicone RMX 1 model implants. An invasive pars plana posterior capsulotomy was necessary in these eyes. We also found that the STAAR silicone RMX 3 model implants were often pitted by the YAG laser during successful posterior capsulotomies. Despite these problems, the STAAR silicone intraocular lens group achieved corrected vision similar to the PMMA lens group.

Humans↗
PubMed1996

Long-term follow-up of three-piece, looped, silicone intraocular lenses.

PURPOSE: To present long-term follow-up of silicone lens implantation. SETTING: Clinique Ophtalmologique, Centre Saint-Victor, Amiens, Cédex, France. METHODS: In this prospective study, we followed 111 eyes consecutively operated on from March 1988 to July 1989. Foldable silicone intraocular lenses (IOLs) were implanted in 107 eyes and poly(methyl methacrylate) (PMMA) IOLs in 4 eyes. The eyes with PMMA lenses were excluded from the study. RESULTS: After a follow-up of 3 years (average 20 months), 13.7% of eyes with posterior capsule opacification (PCO) required a neodymium:YAG (Nd:YAG) laser capsulotomy. In the group with longer follow-up (average 57 months), 40.6% required Nd:YAG capsulotomy. The majority of capsulotomies were performed in the fourth year after surgery. The PCO rate was the same whether the IOL was placed in the sulcus or in the capsular bag (51.5 versus 48.5%). The Nd:YAG treatment caused pitting of the silicone in most cases, with no effect on visual acuity. We did not observe other serious complications such as retinal detachment, endophthalmitis, or silicone discoloration. There was no visual acuity below 20/35. CONCLUSIONS: In this series, the silicone IOLs were compatible with phacoemulsification and did not have a higher rate of complications than has been reported for PMMA IOLs.

Aged↗
PubMed1996

Centration and fixation of silicone intraocular lenses: clinicopathological findings in human autopsy eyes.

PURPOSE: To analyze centration and fixation of three-piece and one-piece silicone intraocular lenses (IOLs) in human autopsy eyes. SETTING: Center for Intraocular Lens Research, Medical University of South Carolina, Charleston. METHODS: Thirty eyes among those submitted to the center between 1986 and 1994 were evaluated. The globes were sectioned at the equatorial plane and photographed from a posterior view. Gross examination was performed to determine IOL type, fixation, centration, and additional pathology. The results were compared with those of a control group of autopsy eyes implanted with one-piece and three-piece poly(methyl methacrylate) (PMMA) IOLs. The control group matched the silicone group in patient age, fixation site, and duration of implantation. RESULTS: Twenty-three eyes (79.3%) had three-piece silicone IOLs and 7 eyes (20.7%), one-piece plate IOLs. Average patient age in the three-piece group was 77.3 years +/- 6.7 (SD) and in the one-piece group, 74.3 +/- 3.8 years. The 30 IOLs were symmetrically fixated in the bag. Average decentration of the three-piece and one-piece IOLs did not differ significantly, 0.37 +/- 0.31 mm and 0.26 +/- 0.13 mm, respectively (P = .37). There was also no significant difference in decentration between the silicone groups and the PMMA groups (P = .93). CONCLUSION: Centration and fixation of silicone IOLs were equivalent to those of standard PMMA IOLs.

Aged↗
PubMed1996

Neodymium: YAG capsulotomy rates after phacoemulsification with silicone posterior chamber intraocular lenses.

PURPOSE: To retrospectively evaluate the incidence of neodymium: YAG (Nd:YAG) laser capsulotomies for posterior capsule opacification (PCO) in eyes receiving one of two types of capsular-bag-fixated silicone posterior chamber intraocular lenses (IOLs) over 7 years. SETTING: John Moran Eye Center, University of Utah, Salt Lake City. METHODS: Four hundred eighty-eight eyes that had cataract extraction with a continuous curvilinear capsulorhexis and implantation of one of two kinds of silicone posterior chamber IOLs were evaluated to assess the incidence of PCO. One hundred thirty-nine received a one-piece, plate-type IOL (Staar) and 349, a three-piece, modified C-loop IOL (AMO). RESULTS: With an average follow-up of 84.3 weeks in the Staar IOL group and 93.5 weeks in the AMO IOL group, the incidence of posterior Nd:YAG laser capsulotomy for PCO was 30.2% and 39.1%, respectively. CONCLUSION: The incidence of Nd:YAG laser capsulotomy after phacoemulsification with implantation of a silicone posterior chamber IOL was still relatively high with long-term follow-up. Although the proportion of patients with a one-piece silicone IOL requiring Nd:YAG capsulotomy was less than that in the three-piece silicone IOL group, the difference was not statistically significant.

Aged↗
PubMed1997

Contrast sensitivity with silicone and poly(methyl methacrylate) intraocular lenses.

PURPOSE: To compare the optical performance of silicone intraocular lenses (IOLs) with that of conventional poly(methyl methacrylate) (PMMA) IOLs. SETTING: University hospital outpatient cataract clinic. METHODS: Ninety-one patients were randomly assigned to receive a PMMA IOL (n = 48 eyes) or a silicone IOL (n = 43 eyes). Contrast sensitivity was evaluated 4 months after surgery using the Vistech sinusoidal-grating chart and the Pelli-Robson letter sensitivity chart. RESULTS: No between-group differences were found using the Vistech test. Using the Pelli-Robson test, mean uncorrected contrast sensitivity was 1.59 log units +/- 0.13 (SD) in the PMMA group and 1.53 +/- 0.15 log units in the silicone group. Mean best corrected contrast sensitivity was 1.67 +/- 0.11 and 1.63 +/- 0.16, respectively. The differences between groups using the Pelli-Robson test were statistically significant (P < .05). No correlation was found between reduced contrast sensitivity and brownish discoloration or thickness of silicone IOLs or posterior capsule fibrosis. CONCLUSION: Contrast sensitivity was lower in patients with silicone IOLs than in those with conventional PMMA lenses.

Adult↗
PubMedDate not supplied

Lumpy silicone-injected breasts: enhanced MRI and microscopic correlation.

Clinical images emphasizing on magnetic resonance imaging (MRI) characteristics of silicone-injected breasts with microscopic correlation were presented. A total of 16 patients with a history of silicone injection breast augmentation received MRI examinations due to palpable masses were reviewed. MRI enables the demonstration of the characteristic MR intensities in silicone-injected breasts. Four breast cancers were accurately detected by the enhancement technique including the cancers admixing within the fibrosis and silicone granuloma. This article can document the excellent ability of MRI with high microscopic correlation in examining these clinical, mammographic and ultrasonographic difficult cases. Understanding the MRI features is helpful to approach these patients. On the other hand, these illustrations indicated the importance of enhancement technique in detecting the cancers and in differentiating the angiogenic lesions from nonenhanced silicone granulomas.

Adult↗
PubMed1996

Fluoride and silicon intake in normal and endemic fluorotic areas.

Precise quantitative information on (a) the contribution of diet to the daily intake of fluoride; and (b) the intake of silicon, which the current work suggests can aggravate fluorosis, is not available for fluorotic and non-fluorotic areas of India. Therefore, an attempt has been made in the present study to collect the above information in normal and fluorotic villages. The daily intake of fluoride (mean +/- SD) over water and diet in normal villages was 1.2 +/- 0.67 mg and 1.0 +/- 0.60 mg, while the corresponding values in a normal urban area were 0.5 +/- 0.03 mg and 1.2 +/- 0.73 mg, respectively. With respect to the intake over water the mean values in normal areas (urban vs. rural) were significantly different (P < 0.001), while there was no significant difference in dietary contribution in the normal areas. In fluorotic villages the daily intake of fluoride was 12.1 +/- 4.11 mg over water and 3.4 +/- 2.43 mg over the diet. These values from fluorotic villages were significantly higher (P < 0.001) than those observed in the normal rural areas. The total intake of silicon (mean +/- SD) in rural and urban normal areas was 204 +/- 58.6 mg and 143 +/- 29.4 mg per day, respectively. The corresponding value from fluorotic villages was 277 +/- 65.5 mg, which was significantly higher (P < 0.01) than those observed in both the normal areas. The situation was similar in fluorotic villages with respect to silicon intake over diet and water. However, the intake of this element over water in the normal rural area (74.0 +/- 18.51 mg per day) was significantly higher (P < 0.001) than the value obtained in the normal urban area (7.5 +/- 1.82 mg per day). This study clearly shows that in the fluorosis-affected areas studied, (a) the total intake of both fluoride and silicon is significantly higher than the intake in non-fluorotic areas; and (b) diets contribute significantly to the intake of both these elements. Our observations on silicon intake and its probable relation to fluorosis are the first of their kind in the literature.

Diet↗
PubMed2002

Recording and marking with silicon multichannel electrodes.

This protocol describes an implementation of recording and analysis of evoked potentials in the hippocampal cortex, combined with lesioning using multichannel silicon probes. Multichannel recording offers the advantage of capturing a potential field at one instant in time. The potentials are then subjected to current source density (CSD) analysis, to reveal the layer-by-layer current sources and sinks. Signals from each channel of a silicon probe (maximum 16 channels in this study) were amplified and digitized at up to 40 kHz after sample-and-hold circuits. A modular lesion circuit board could be inserted between the input preamplifiers and the silicon probe, such that any one of the 16 electrodes could be connected to a DC lesion current. By making a lesion at the electrode showing a physiological event of interest, the anatomical location of the event can be precisely identified, as shown for the distal dendritic current sink in CA1 following medial perforant path stimulation. Making two discrete lesions through the silicon probe is useful to indicate the degree of tissue shrinkage during histological procedures. In addition, potential/CSD profiles were stable following small movements of the silicon probe, suggesting that the probe did not cause excessive damage to the brain.

Animals↗
PubMed2001

Experimental factors controlling analyte ion generation in laser desorption/ionization mass spectrometry on porous silicon.

Desorption/ionization on porous silicon (DIOS) is a relatively new laser desorption/ionization technique for the direct mass spectrometric analysis of a wide variety of samples without the requirement of a matrix. Porous silicon substrates were fabricated using the recently developed nonelectrochemical H2O2-metal-HF etching as a versatile platform for investigating the effects of morphology and physical properties of porous silicon on DIOS-MS performance. In addition, laser wavelength, mode of ion detection, pH, and solvent contributions to the desorption/ionization process were studied. Other porous substrates such as GaAs and GaN, with similar surface characteristics but differing in thermal and optical properties from porous silicon, allowed the roles of surface area, optical absorption, and thermal conductivities in the desorption/ionization process to be investigated. Among the porous semiconductors studied, only porous silicon has the combination of large surface area, optical absorption, and thermal conductivity required for efficient analyte ion generation under the conditions studied. In addition to these substrate-related factors, surface wetting, determined by the interaction of deposition solvent with the surface, and charge state of the peptide were found to be important in determining ion generation efficiency.

Hydrogen-Ion Concentration↗
PubMed2006

Dehydrogenative silane coupling on silicon surfaces via early transition metal catalysis.

Derivatization of silicon surfaces is an area of intense interest due to the centrality of silicon in the microelectronics industry and because of potential promise for a myriad of other applications. In this paper, we investigate the feasibility of Si-Si bond formation directly on the surface to contrast with the more widely studied Si-C and Si-O bond forming reactions. Functionalization of hydride-terminated silicon surfaces with silanes is carried out via early transition metal mediated dehydrogenative silane coupling reactions. Zirconocene and titanocene catalyst systems were evaluated for heterocoupling of a molecular silane, RSiH3, with a surface Si-H group on Si(s). The zirconocene catalysts proved to be much more reactive than the titanium system, and so the former was examined exclusively. The silanes, aromatic or aliphatic, are bonded to the silicon surface through direct Si-Si bonds, although the level of incorporation of the trihydroarylsilanes was substantially higher than that of the aliphatic silanes. The reaction proceeds on nanocrystalline hydride-terminated porous silicon surfaces, as well as flat Si(100)-H(x) and Si(111)-H interfaces. The reactions were studied by a variety of techniques, including FTIR, SIMS, and XPS.

Catalysis↗