A crossed beams apparatus for study of thermal energy neutral-neutral reactions is described. The detector comprises a high efficiency (∼0.1%) electron bombardment ionizer, quadrupole mass filter, scintillation ion counter, and gated scalers synchronized with the beam modulation. The ionizer is nested within three chambers, each pumped by a separate ion pump and the innermost attached to a liquid nitrogen trap. The design is such that molecules which pass through the ionizer without being ionized fly on into another differentially pumped region before hitting a surface. The entire detector unit, including pumps and trap, is mounted on a rotatable platform (angular range ∼140°) which forms the lid of the scattering chamber. The beam sources also comprise modular units, mounted in differentially pumped side chambers which insert into ports in the scattering chamber. Angular distributions of reaction products have been measured for several reactions of Cl, Br, or D atoms with halogen molecules or hydrogen halides. Product velocity distributions have also been measured by time of flight for some of these reactions. In most cases, the partial pressure of interfering background species in the ionization region was ⪝ 10−15 Torr, and satisfactory data could be obtained with reactive scattering signals of a few counts per second.

We have studied the infrared spectra of the bound and photodissociated states ofMb-"2CO and Mb-'3CO from 5.2 to 300 K. The absorbance peaks seen between 1800 and 2200 cm-1 correspond to CO stretching vibrations. In the bound state of Mb-'2CO, the known lines A0 at 1969, A1 at 1945, and A2 at 1927 cm-1, have center frequencies, widths, and absorbances that are independent of temperature between 5.2 and 160 K. Above 160 K, A2 gradually shifts to 1933 cm-'. The low-temperature photodissociated state (Mb*) shows three lines (BO, B1, B2) at 2144, 2131, and 2119 cm-' for "2CO. The absorbances of the three lines depend on temperature. Bo is tentatively assigned to free CO in the heme pocket and B1 and B2, to CO weakly bound to the heme or heme pocket wall. The data are consistent with a model in which photodissociation of MbCO leads to B1 and B2. B2 decays thermally to B1 above 13 K; rebinding to A occurs from B1. The barriers between B2 and B1 and between B1 and A are described by activation enthalpy spectra. Heme and the central metal atom in state Mb* have near-infrared, EPR, and Mossbauer spectra that differ slightly from those of deoxyMb. The observation of essentially free CO in state B implies that the difference between Mb* and deoxyMb is not due to an interaction of the flashed-off ligand with the protein but is caused by an incomplete relaxation of the protein structure at low temperatures.The reversible binding of CO to the storage protein Mb can be studied with flash photolysis (1). Experiments in which the Soret line was monitored demonstrate that the binding process involves a number ofsteps (2, 3). Here we show that monitoring the CO stretching vibration reveals additional features of the protein's interior.The active center of Mb, the heme group, is embedded in the protein (Fig. 1) (4) and the ligand binds at the central heme iron. In flash photolysis, the bound-state MbCO is photodissociated. Below 200 K the CO cannot leave the heme pocket and rebinds from there. Two states are involved in low-temperature recombination: state A, in which the CO is bound, the heme is nearly planar, and the iron atom has spin 0; and state B, in which the CO is photodissociated from the heme iron and remains in the protein pocket and the iron has spin 2. At low temperatures, the rebinding process B to A is not exponential in time. We have explained this observation by postulating the existence of conformational substates (2, 5). At low temperatures each Mb molecule is frozen into a particular substate with a specific barrier height for rebinding. From 180 to 80 K the transition occurs by an over-the-barrier Arrhenius process; below 60 K, quantum mechanical tunneling dominates (6, 7). State B (Mb*) has been studied in MbCO and CoMbCO by near-infrared (8, 9), EPR (10, 11), and Mbssbauer (12) Pentex (Kankakee, IL) was dissolved in 70% (vol/vol) glycerol in water buffered to pH 7 with 0.1 M phosphate. The sample was stirred under a CO atmosphere for several hours, reduced with sodium dithionite, and stirred for s...

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This article contributes to the literature on reflexivity by articulating a queer reflexivity lens, which entails engaging in a reflexive questioning of the categories we use to identify people and recognizing the shifting nature of researcher and participant identities over the course of the research process. Queer reflexivity enables us to think differently about an important debate in qualitative methods concerning who can study whom. For instance, are white researchers in a position to study people of color? Are men able to study women and women's issues? Can "straight"-identified researchers study the Lesbian, Gay, Bisexual, Transgender and Queer community? I argue that the question of whether or not to "match" for categories of difference in research studies is complicated by the fluid, shifting nature of identities that queer theory highlights. In order to demonstrate how qualitative organizational researchers can learn about the craft of research through the concept of queer reflexivity, I recount an auto-ethnographic "coming-out" tale in which I discuss the implications of my shifting sexual identity over the course of a research project.In the spirit of reflexivity, a central concept in this article, I am going to start off with two stories about how my social identities have mattered in my research. First, in July 2010, I was attending the biannual Gender, Work, and Organization Conference at Keele University. As a scholar who examines how social identities such as gender matter in organizational life, the theme of this conference very much resonated with me and my research interests. Despite being somewhat surprised that I was one out of only a handful of men among over 300 participants who were attending this conference, I did not seriously reflect on how others at the conference may have been perceiving me as a white man. Not until a conversation with a colleague during lunch. When I told her that I was interviewing women nursing students as part of my research, she asked, "How can you study women? I wouldn't feel comfortable studying men." Her comment surprised me, as this was the first time that I had been *This article won 'The Most Thought-Provoking Ph.D. Paper' Award at the 2012 Qualitative Research in Management conference.

Much existing research has shown that men are able to construct and enact masculine identities in female‐dominated occupational contexts. However, few studies have examined the experiences of both men and women in these occupations. Furthermore, few studies attend to how men and women in these occupations both conform to and resist gender norms. In this study, I draw on the undoing gender frameworks developed by Deutsch and Butler to address the limitations mentioned above. Most notably, this study attends to the ways in which male and female nursing students do gender by conforming to dominant gender norms, as well as undo gender by resisting these norms. The main contribution of this study is thus to show the multiple ways through which gender can be done and undone in the professional training of both male and female nurses. The results of this study demonstrate the importance of attending to both women and men in research on female‐dominated occupations and of examining both similarities and differences in the gender performances of men and women.