What does teaching and scholarship look like at the Elucidarium?
Teaching and scholarship at the Elucidarium aren't unrecognizably different from a real-world university, though the curricula for students are significantly more fluid. Scholars at the Elucidarium might be focused purely on research, or they might spend more time teaching and mentoring instead. Many will combine a little of both. Research often involves the use of the Library and its vast collections, but can also be experimental. The university offers facilities for different kinds of experiments and demonstrations in natural philosophy and magic. For those teaching and studying medicine, hands-on study and demonstrations usually take place at the Jumana Bimaristan instead.
Most Elucidarium students will have their studies guided by a mentor, who might be a full-time professor, a resident scholar, or a physician dividing their time between the hospital and the university. This mentor will often help the student decide what classes to take and particular studies to pursue, and may offer additional opportunities in the form of special discussions and debates, research in the mentor's own collection of materials, or assisting in the mentor's particular field of practice.
Depending on the subject, teaching may emphasize either theory or practice, or offer a combination of the two. A newer student's learning is often done in a classroom, where lectures are given by an Elucidarium professor. Further on in their academic career they may spend time in smaller groups of students, focusing on more specialized topics where the professor will engage them in deeper discussion and research.
Due to this flexibility, people may come to the Elucidarium for either a liberal education or a highly focused and specialized one. Whatever kind of advanced education a person wants, it can generally be arranged so long as the right teachers and courses of study are available.
Of course, the Elucidarium is an institution rather full of its own self-importance (unfortunately, if justifiably to some extent), and acceptance as a student is very often limited to those with either money or connections, or both. This doesn't mean that people from poorer or more marginal backgrounds can't get in, but it does render that more difficult. The Temple of Storms complex actually does offer some opportunities for higher education as well, but with fewer resources and on a significantly less exalted level. Nevertheless, it's often a valuable option for those who find acceptance at the Elucidarium challenging, including people of lesser means, those of non-Sirdabi/Irzali heritages (these two tending to be disproportionately favored at the Elucidarium), non-Azadi, and a great many women who enjoy the expanded availability of mentorship from the Temple's many female teachers. Though it lacks the glittering reputation of the Elucidarium, the Temple school has produced a number of well-respected scholars, academics, and specialized practitioners, especially in pharmacology, horticulture, art and design, and various schools of divination and spiritualism.
Is the Library, or at least parts of it, open to the general public? Can reading material be borrowed or leave the premises? I assume the Library and its contents are carefully guarded?
The Library's actual collections aren't open to the general public, but there is a research and reading room where visitors can peruse a (typically significantly redacted) list of the Library's collections and request a given work be brought to them. Greater reputation and credentials as a scholar will open up increasing levels of access to the collections. The original texts belonging to the library will almost never leave it, but researchers can request that a copy be made of any text they are interested in.
The Library and its contents are in fact carefully guarded, both by actual guards and -- so it's said, anyway -- devices or spells that prevent access to all but authorized persons.
Edited to add: There is a "general access" part of the library for students and faculty of the Elucidarium, where mostly relatively common volumes or copies of more unusual texts can be handled and read. A visiting researcher could be granted access to this as well, but they would probably not find it as useful since rarer and more specialized texts for the most part aren't available there. Faculty and higher-level students can borrow these books for a short period of time, but stealing a book even from this part of the library is still a crime (not punishable by death in this case, thankfully) so there's substantial responsibility involved in having one of them in your possession. Regardless, nothing from the Library's collections may be removed from the Elucidarium grounds except for copied works that have been created and authorized by the Library staff.
Does the Library have dedicated librarians to maintain the archives and assist visiting students/scholars/researchers?
It certainly does! There are a host of librarians of various ranks who care for the collections and assist researchers in gaining access to the texts they're interested in. Librarians are also a watchful presence in the research room, ensuring that researchers treat the texts properly, do not mark or mishandle them, and above all, don't steal any part of them. Specialized scholar-librarians are part of the library staff too, who perform administrative duties along with their research, and help researchers with specialized projects.
How do the Elucidarium's studies in magic overlap with or relate to the work of the Collegium of Mages and the Poets' and Calligraphers' Guild?
The most commonly taught magic at the Elucidarium, and the most respected, is astrological divination. A course of study in this will allow the graduate to draw up horoscopes, discern the predominant celestial conditions at any given time and intuit how they are presently influencing sublunary affairs, and make predictions of the future according to the motions of various celestial bodies, among other things. Not surprisingly, a focus on astrological magic is usually paired with the study of astronomy.
Other spiritual magics are also taught and researched at the Elucidarium, which often involve the attempted study of other spheres of existence (such as those of the Slumberland and Otherland below the mortal realm, or the aethereal realm above it), along with the harnessing of their energies or communication with various beings that might dwell in these other spheres (such as ghosts, jinn, angelic beings, or even demons). Also perhaps not surprisingly, such studies tend to be talked about less outside the Elucidarium and are not granted the nearly universal respect that astrological magic is.
Arcane magic is also taught to some extent, typically in its more traditional form focusing on the study and minor manipulation of the major elements. As taught at the Elucidarium, arcane magic is much more conservative in its theory and practice than it is at the Collegium of Mages, and most mathemagi scoff at it for what they see as its laughably old-fashioned nature.